Lithium is thought to be one of the first elements made after the Big Bang. An enormous amount of Hydrogen, Helium, and Lithium (the first three elements on the periodic table) were synthesized within the first thee minutes of the universe’s existence.

This process is called Big Bang nucleosynthesis. Essentially, all elements heavier than lithium were made much later by stellar nucleosynthesis (like what is happening in the Sun).


Lithium is special for other reasons too

Lithium facts on history

Lithium is from Greek lithos meaning “stone”

Was used in the first man-made nuclear reaction in 1932

Lithium interesting facts

Soft enough to be cut by scissors

The lightest metal, and least dense solid element, so it can easily float on water

Does not occur freely in nature (it’s too unstable), but is found in nearly all lava, mineral water, and sea water

Pure lithium corrodes immediately when exposed to the moisture in air

Lithium in biology

18650 3.7V

All organisms have a little lithium in their bodies, but it does not seem to serve a biological purpose

Lithium in pills is used to treat bipolar disorder

Lithium in economics

80% of the world’s lithium is in salt flats between Argentina, Chile, and Bolivia


Let’s look at some pictures


Here are some pieces of raw lithium. Notice the lines and grooves cut into the soft metal by the tool they used to cut it. Also note what appears to be a bubble. It is most likely Hydrogen, as this is what is released when lithium reacts to water (or water from moisture in the air).

Lithium cell

This is a photograph taken in Bolivia, in what is called ‘Salar de Uyuni’ – the biggest salt lake in the world. The amazing scenery holds a secret – a huge reserve of lithium. With the right investment, Bolivia may become what Kuwait was for oil to the new rechargeable revolution.

18650 lilon battery

A fully developed lithium mine in the Atacama Desert. This is where the material in your 18650 battery most likely comes from.

asteroidc and li

This is a depiction of Asteroid 2012 DA14 which nearly missed Earth a few years ago. It was once famously valued at $195 billion US dollars for the large amount of metals like iron ore, copper, and lithium trapped inside. Maybe one day we won’t have to dig up our backyard to get the resources we need to enjoy ourselves.

So remember, next time you turn on your vaporizer, or other machine that uses li-ion batteries, to think a little about where it came from and what it means for our future.



What is a UPS?

A UPS (Uninterruptible Power Supply) ensures that users can save data in emergency situations to avoid unnecessary losses due to power outages. This is a technology developed for power grids, network and medical systems, and other systems that rely on a centralized power supply of a network of computer systems.


Advantages of EPS (Emergency Power Supply)

An EPS (Emergency Power Supply) has a conversion time that is generally in the millisecond level (2ms-250ms), which fluctuates according to different load characteristics to ensure the timeliness of power supply;

It has strong load adaptability, including capacitive, inductive, and hybrid loads, and strong overload and shock resistance;

There are multiple outputs to prevent failure caused by a single output;

There are fire linkage and remote control signals, which can be switched between manual and automatic;

It can adapt to its environment.  It is suitable for a variety of harsh environments with measures to prevent failure in high and low temperatures and hot and humid environments.  It can work against, salt spray, dust, vibrations, and rat bites;

An EPS has a long service life, fast battery charge, and management capabilities.


Differences between an EPS’s backup power and UPS’s power


An EPS is mainly used in electrical equipment for the fire protection industry.  It is used for those who look for a continuous power supply that can be used in an emergency in case of sudden power grid failure.

A UPS is generally used for precision instrument loads (such as computers, servers and other IT industry equipment), which require a high power supply quality.  It is used for those who look for certain requirements, such as a quick switch-over time to an inverter, output voltage, frequency stability, and purity of output waveforms.



An EPS generally does not have high requirements for a switch-over time to an inverter. Special applications have certain requirements. There are multiple outputs and monitoring and detection functions for each output and a single battery. The daily focus is on bypassing a power supply and switching to an inverter only when the main power fails, and the power utilization rate is high.

The On-Line UPS has only one total output and generally emphasizes its three major functions:

Voltage and frequency stabilization

A quick switch-over time

The rectifier / inverter double-conversion circuit: The inverter is switched to bypass the power supply only when the inverter fails or is overloaded.

The power utilization rate is not high (generally 80-90%). However, some places in European and American countries, where power grids and complete power supplies are used, have switched over to a UPS with a short switch-over time to an inverter (less than 10ms) to save energy.



An EPS mainly provides power for power protection and fire safety. The load has both inductive, capacitive, and rectified non-linear loads, and some loads are only put into operation after the power supply is cut off. Therefore, EPS is required to provide a large inrush current, good output dynamic characteristics, and a stronger anti-overload. A UPS, on the other hand, mainly supplies power to computers and network equipment, and the nature of the load (input power factor) is not much different.

The main purpose of a UPS is to maintain the transferage of information, and the main purpose of an EPS is to prevent major disasters. In other words, a UPS focuses on saving data while an EPS mainly focuses on saving people. Generally, EPS power is large, and the inverter in the machine is in a standby state.

EPS power inverters have a larger redundancy: both the incoming and outgoing cabinets are inside the EPS, and the motor loads are started with variable frequency. The casing and wires are flame retardant, and there are multiple ways to input power, which can be linked with fire protection. An EPS power load is also generally inductive and resistive. It can come with motors, lighting, fans, pumps, and other equipment.

UPS power inverters, on the other hand, have a relatively small redundancy, do not need to be flame retardant, and have no mutual investment function. A UPS power load is also a capacitive load. The main belt device is usually a computer, which is mainly used in computer rooms to ensure uninterrupted power supply and voltage stabilization.


Different power supplies

A UPS prioritizes an inverter to ensure its power supply while an EPS prioritizes city power to ensure saving energy. There are differences in the design specifications of the rectifier / charger and the inverter.

An EPS uses an offline power supply; unfortunately, when the utility power fails and an EPS cannot be powered by the emergency battery, it cannot do anything, and consequences are dire.

A UPS is on-line. Even if there is a power failure, it can be alarmed in time. With the backup power in city power supply, the user can grasp the power failure in time and eliminate it without causing greater losses.


Precautions against using a UPS

A UPS should be used in a well-ventilated and clean environment to facilitate heat dissipation.

Do not carry inductive loads, such as money counters, fluorescent lamps, air conditioners, etc., to avoid damage.

The output load control of a UPS is best at around 60%, and the reliability is the highest.

A UPS with a light load (such as a 1000VA UPS with a 100VA load) may cause deep discharge of the battery, which will reduce the battery life and should be avoided as much as possible.

Appropriate discharge can help the activation of the battery. For example, if the main power is not interrupted for a long period of time, the main UPS should be manually disconnected and discharged once every three months.

A small-sized UPS can generally be on and off when the employees are at and off work respectively. A UPS in a network room must run around the clock, however, since most networks work 24 hours.

A UPS should be charged after discharging to prevent the battery from being damaged due to excessive self-discharge.

The material and chemistry used in the cathode of a battery are vital in determining the battery performance. Currently, the positive electrode materials successfully developed and applied include lithium cobalt oxide (LCO), lithium iron phosphate (LFP), lithium manganate (LiMn2O4), ternary material nickel cobalt manganate (NCM), and nickel cobalt aluminum aluminate (NCA). We will explore a few common chemistries for cathode material in this article.


  • Lithium cobalt oxide (LCO, LiCoO)

Lithium cobalt oxide, also known as lithium cobaltate, are particularly special because they were the first commercially produced lithium batteries. Lithium cobaltate has many benefits with its high discharge platform, simple synthesis process, high capacity, and good cycle performance.  However, cobalt can be relatively toxic, and the price high.  It is also difficult to guarantee safety when making large LCO batteries.

Most 3C electronic batteries still use LCO rather than a higher-capacity ternary material because lithium cobalt oxide material has greater density per volume. Lithium cobalt oxide is predominantly used in cell phones and laptops.

Furthermore, the theoretical capacity of lithium cobalt oxide is high, but the actual capacity is only half of what is theorized. The reason is due to the charging process: when the amount of lithium ions extracted from lithium cobalt oxide material is less than 50%, the morphology and crystal form of the material can be kept stable.  However, when the lithium-ion extraction amount increases to 50%, the lithium cobaltate material undergoes a phase change. If charging continues at this time, cobalt will dissolve in the electrolyte and generate oxygen, which affects the stability of the battery cycle life and performance.


  • Lithium iron phosphate (LFP, LiFePO4)

There is wide interest in Lithium iron phosphate cathode materials.

Its main features include non harmful elements, low cost, and good safety and cycle life (its lifespan can reach 10,000 cycles). These characteristics have made lithium iron phosphate materials popular for research, and they are widely used in the field of electric vehicles.

The main disadvantage of lithium iron phosphate is its low energy density. The voltage of lithium iron phosphate material is only about 3.3V, which makes the LFP battery have lower energy storage. Lithium iron phosphate also has poor conductivity and needs to be nanometer-sized. It can be coated to obtain good electrochemical performance, which makes the material become “fluffy” and the compaction density low. The combined effect of the two makes the energy density of lithium iron phosphate batteries lower than that of lithium cobalt oxide and ternary batteries.

Recently, accidents concerning new energy vehicles have occurred and frequently show up on the news. People hope to improve upon the materials and its safety performance by modifying it: some researchers have mixed lithium iron phosphate with manganese to make it have higher voltage and energy density while others have mixed it with NCM ternary material.


  • Ternary materials (NCM, NCA)

Ternary material is the common name of lithium nickel cobalt manganese oxide (LiNixCoyMn1-x-y02), which is very similar to lithium cobaltate. This material can be balanced and adjusted in its specific energy, cycle, safety, and cost.

The different configurations of nickel, cobalt, and manganese bring about various properties to the material: increasing the nickel content increases the capacity of the material but makes the cycle performance worse; the presence of cobalt makes the material structure more stable but the content too high and capacity reduced; the presence of manganese reduces costs and improves its safety performance, but its high content destroys the layered structure of the material.

Due to the many factors that need to be considered when using these elements, the focus of ternary material research and development has been on finding the proportional relationship between nickel, cobalt, and manganese in order to achieve optimal performance.


If you are interested in the Himax’s high discharge and custom-made batteries, please reach out to us at We can be the one-stop solution to your products’ needs.

Forklift Battery

Forklift Battery

A forklift battery actually has two functions:


  1. To provide a power source to the forklift.
  2. The lesser-known function is to provide mass as a counterweight, which aids the forklift’s lifting capacity.


The most common forklift batteries are Lead Acid, but a trend to use Lithium iron phosphate replacement battery due to advantages of higher capacity, safety, and more cycles, etc.

Forklift LiFePO4 Battery

However, we found that there are more forklift customers are require LiFePo4 battery and a few low-temperature requirement. For a simple comparison:

  • Price

Lead-Acid battery: $$$


LiFePO4 battery: $$$$$$$$$$


  • Features

LiFePO4 battery > Lead Acid battery


Let’s take an example if the working environment is the low temperature like freezer inventory, so Lithium iron phosphate must be better due to working at low temperatures for a long time, and low-temperature charging required.


  • Weight

Lead-Acid battery: More Heavy (70kg and 80kg per kWh of usable capacity)


LiFePO4 battery: Lighter (10kg and 15kg per kWh of usable capacity)


  • Cost per cycle

LiFePO4 battery (more charge & discharge cycles) > Lead Acid battery


12v Forklift Battery

The cycles count of traditional Lead-acid battery is around 500–600 times, LiFePO4 battery is around 2000 times (The promise cycles of Grepow Lithium iron phosphate battery is 1500 times / 3 years)


In addition to the high initial cost of Lithium iron phosphate battery, it is free of replacement and maintenance cost, that’s why LiFePO4 battery is more economical than Lead Acid even higher initial cost.

Drones Battery

Whether you are planning to buy a RC drone as a gift to gift someone or want to buy one to fly in your leisure time, some mini RC drones with hidden camera options that can be used as a    spy video camera, others with LED blades that can be flown at night. With so many designs and features to choose, following are some useful tips for buying some of the best RC drones available from the market:

 Drones Battery

Ready- Made vs Build-Your-Own

For teens, RC drones can be a wonderful hobby. It allows them to go outside and develop technical skills to operate various types of gadgets and vehicles.  For adults, flying these drones can be a great way to relieve stress from work and studies. Comparing to other RC gadgets and vehicles RC drones can be quite complicated to operate.Therefore, you need to practice a lot before flying them outdoors. On the other hand,  before buying an RC drone, you need to choose between ready-made or build-your-own option.

Ready-made RC drones are perfect for those who wish to fly one without considering technical and mechanical sides. Ready-made RC drones are usually preferred by newbie’s as it is easier to operate than build-your-own drone.

Those people who prefer an RC drone kit and build it from scratch are usually those who are interested in exploring everything about their RC drones. If you build one by yourself,  you can even customize it and improve its performance. However, bear in mind that it requires a lot of time, patience and efforts.

Rc battery

Gas and Electric Powered RC Drones

Generally speaking, RC drones that run on gas are more rare and expensive than electric ones. They are also more complicated to operate and fly.

Electric ones are less expensive than gas powered RC drones and can be easily operated outdoors. Although their battery packs can be quite expensive, however, they are easier to maintain and operate.


Indoor and Outdoor Drones

Indoor RC drones are perfect for newbie’s and amateur players as they are not as powerful as outdoor RC drones. Moreover, they can only go up to a certain level as they are meant to be used indoors.

Also, you need to make sure that no obviously objects or pets getting into your road when flying RC drones indoor.

Outdoor RC drones are more expensive and powerful than indoor drones and can be easily operated from a wide distance.

Outdoor drones are not recommended for new players as they can harm travelers or vehicles if they get crashed from a high height.


Mini vs Large Drones

RC drones come in a variety of shapes and sizes. Smaller RC drones do not cause any severe damage in case of an accident. They are quite versatile and can be flown indoors and outdoors as well. They’re perfect for new players and do not require much time to set up.

However, they are not as sturdy as bigger RC models.

Larger drones are more suitable for professional players. They closely resemble real helicopters and can be easily flown in windy places.

Bigger models can be quite expensive and you need to follow certain rules while flying such drones outdoors.

RC drones battery

LED Blades for RC Drones

RC drones are equally fun when flown at night. You can use special blades that consists of bright neon and LED lights for a better night vision. You can even customize your blades yourself with LED strips. Whether you are flying your drone during the day or night time, try to avoid flying them in public places.


Maintenance and Repair

The maintenance of an RC drone includes changing the motor and preventing it from overheating. For beginners, it is recommended to seek for some professional help in case a drone is damaged or is not properly working.

A battery with lower C rate can negatively affect the speed and overall performance of your drone. In order to maximize the life cycles of your drone’s battery, please wait for at least half an hour to recharge your drained battery. Also, avoid overcharging it.

You can also join an online website or group to get valuable insights and information regarding RC drones. You can follow various threads and blogs to get updates and reviews for the latest RC drone kits.



Keep an eye out on Grepow’s official blog, where we regularly update industry-related articles to keep you up-to-date on the battery industry and related peripheral market.


3 min read . Updated: 31 Oct 2016, 01:56 PM IST

Naomi Tajitsu, Norihiko Shirouzu

Toyota is all set to enter the growing all-electric car market having technology edge of lithium-ion battery that could equip it with more power without significant extra cost.


Toyota City, Japan: Engineers at Toyota Motor Corp say they have tamed volatile lithium-ion battery technology, and can now safely pack more power at no significant extra cost, giving the Japanese automaker the option to enter the growing all-electric car market.

While rivals including Tesla Motors and Nissan Motor Co began adopting lithium-ion battery technology nearly a decade ago, Toyota has largely held back due to concerns over cost, size and safety.

Lithium-ion batteries can be unstable and have been blamed for incendiary Samsung smartphones and smoking Dreamliner airplanes.

Having Toyota endorse lithium-ion will be a fillip for the developing technology, and gives the automaker the option to produce for an all-electric passenger car market which it has avoided, preferring to put its heft behind hydrogen fuel-cell vehicles (FCVs).

Toyota says its Prius Prime, a soon-to-be-launched plug-in electric version of the world’s top-selling gasoline hybrid, will use lithium-ion batteries, with enough energy to make the car go around 60 kms (37.3 miles) when fully charged before the gasoline engine kicks in. Because of different methodology in measuring a car’s electric mode range, the Prime’s 60 km range will be listed in the United States as around 25 miles (40.2 kms).


‘Safety, safety, safety’

Many lithium-ion car batteries use a chemical combination of nickel, cobalt and manganese. These store more energy, take a shorter time to charge, and are considered safer than other Li-ion technologies. But they can still overheat and catch fire if not properly designed, manufactured and controlled.

“It’s a tall order to develop a lithium-ion car battery which can perform reliably and safely for 10 years, or over hundreds of thousands of kilometers,” said Koji Toyoshima, the chief engineer for the Prius.

“We have double braced and triple braced our battery pack to make sure they’re fail-safe … It’s all about safety, safety, safety,” he told Reuters.

Toyota has mainly used the more mature nickel-metal hydride batteries to power the motor in the conventional Prius, widely regarded as the forefather of the ‘green’ car, though it did use some lithium-ion batteries from 2009 in its first plug-in hybrid Prius, around the time the first all-electric cars powered by lithium-ion batteries – such as the Tesla Roadster and Nissan Leaf – came on to the mass market.

Toyota’s confidence in its battery’s safety and stability comes from improved control technology that precisely monitors the temperature and condition of each of the 95 cells in its new battery pack.

“Our control system can identify even slight signs of a potential short-circuit in individual cells, and will either prevent it from spreading or shut down the entire battery,” said Hiroaki Takeuchi, a senior Toyota engineer involved in the development.

Working with battery supplier Panasonic Corp – which also produces Li-ion batteries for Tesla – Toyota has also improved the precision in battery cell assembly, ensuring battery chemistry is free of impurities.

The introduction of even microscopic metal particles or other impurities can trigger a short-circuit, overheating and potential explosion.

“The environment where our lithium-ion batteries are produced is not quite like the clean rooms where semiconductors are made, but very close,” Takeuchi said.

Battery experts say increasingly sophisticated systems that can track individual cell conditions are becoming closely-held trade secrets.

“State of charge management, safety management and algorithm development is becoming one of the higher tiers of proprietary internal development,” said Eric Rask, principal research engineer at Argonne National Laboratory, a US department of energy facility outside Chicago.

“It’s very internal, very strategic, and companies are seeing management algorithms as a competitive advantage.”


Falling prices

Toyota has also been able to shrink the size of each cell, for example, closing the distance between the anode and cathode, where active ions travel when charging and discharging.

This has doubled battery capacity to around 8.8 kilowatt hours, while only increasing the battery pack size by around two-thirds and its weight by a half.

Battery experts say lithium-ion battery cell prices have fallen by about 60% in five years to around $145 per kilowatt hour as larger-scale production has made them cheaper to make.

Falling battery prices have enabled Toyota to develop its more compact, efficient battery, while also adding more sophisticated controls into its battery pack, Toyoshima said. Toyota declined to say more on its costs.

While Toyota sees FCVs as the ultimate ‘green’ car, the United States and China are encouraging automakers to make more all-electric battery cars as they push alternative energy strategies.

“Developing lithium-ion batteries for both hybrids and plug-ins will enable us to also produce all-electric cars in the future,” said Toyoshima said. “It makes sense to have a range of batteries to suit different powertrains.” Reuters.

Several NiMH replacement hybrid car batteries we recommend.

Click the link to view



It has a lot of benefits to solar street lights with lithium batteries. So more and more countries and areas are planning to use solar street lights with a lithium battery.

A small solar panel, after absorbing one-day solar energy, produces enough electricity for a 30 Watt LED solar street light to last 2–3 days. Compared with traditional street lamps, solar street lights with lithium batteries can save a lot of electric energy and can reduce the consumption of electric energy when no one passes, without human control. Some years ago, solar street lights use lead-acid battery or gel battery, these batteries are heavy, the DOD is 70%, low efficiency, and easy to steal by theft. Solar street lights with lithium battery, the lithium battery is light and DOD is 100%, more efficient, and can install on the top of the pole or fix inside the lamp, it has an anti-theft function.


The reduction of advanced control technology and energy consumption, coupled with the development of solar street lights technology and lithium battery technology, has gradually replaced solar street lights with lithium batteries with traditional street lights.

A 250W traditional street lamp lights up for 10 hours a day, and need consumes about 100 KWh a year. Installing 30 Watt LED solar street light can achieve the same light efficiency, so installing solar street lights with lithium battery can save at least 80% of the electricity bill. Solar street light Philippines are widely used. The lighting conditions in this area are good, there are many islands, many places are too far away to be connected to the mains, and most of them are tourist areas. The installation of solar street lights will also help the tourism activities of these places. So the benefits of solar street lights with a lithium battery will include high efficiency, long use life, save a lot of power and anti-theft.


2 min read . Updated: 21 Jan 2020, 09:32 AM IST

Swansy Afonso , Bloomberg


▪ Prime Minister Narendra Modi’s administration unveiled a slew of measures in 2019 to promote the clean-energy vehicles

▪ Several plans are under way to build lithium-ion battery factories in India





  • Electric vehicles

MUMBAI : India’s ambition of becoming a global hub for making electric vehicles faces one major hurdle: its lack of access to lithium.


Home to some of the most polluted cities on the planet, the South Asian nation is pivoting toward new-energy vehicles to clean up its toxic air. But with meager resources of lithium, the mineral essential to make batteries for electric vehicles, it is having to scour for resources overseas.


India’s EV production will rely on imports from China of lithium chemicals used to make cathodes and battery cells, according to Jasmeet Singh Kalsi, director at Manikaran Power Ltd., which is exploring setting up India’s first lithium refinery. “China has a thriving lithium chemical, battery cathode, battery cell and EV supply chain. India has none.”


Prime Minister Narendra Modi’s administration unveiled a slew of measures in 2019 to promote the clean-energy vehicles, including a $1.4 billion plan to make India a manufacturing hub for EVs and cutting taxes to spur purchases. While electric cars in India remain a small segment, with an estimated 3,000 sold in 2018 compared with the 3.4 million fossil fuel-powered cars in the same year, the nation is forecast become the fourth-largest market for EVs by 2040, when the segment will comprise nearly a third of all vehicles sales, according to BloombergNEF.


  • Import Reliance

Several plans are under way to build lithium-ion battery factories in India. Meanwhile, China — the largest electric vehicle market in the world — is dominant in the battery supply chain. Around three-quarters of battery cell manufacturing capacity is in China, and Chinese companies have unparalleled control of required domestic and foreign battery raw materials and processing facilities, according to BNEF.


“Indian companies have been involved in trying to prospect for stakes in overseas resources, and possibly on-shoring more raw materials production capacity in India,” said Sophie Lu, head of metals and mining for BloombergNEF. “But there are very little synergies right now because further up the value chain, battery components manufacturing capacity does not seem to be planned extensively for India.”


A joint venture called Khanij Bidesh India Ltd. has been formed between three state-run companies — National Aluminium Co., Hindustan Copper Ltd. and Mineral Exploration Corp. — to acquire lithium and cobalt mines overseas. Amara Raja Batteries Ltd., the country’s second-biggest traditional battery maker by value, will build a lithium-ion assembly plant, while Suzuki Motor Corp. along with Toshiba Corp. and Denso Corp. is setting up a lithium-ion battery manufacturing plant.


Manikaran signed an agreement with Australia’s Neometals in June to jointly fund the evaluation of developing a lithium refinery in India with a capacity of 10,000 tons to 15,000 tons of the finished product. That capacity falls short of India’s projected requirement of 200,000 tons of lithium hydroxide by 2030, Kalsi said.


Electric vehicles are “slowly going to take off, not with the speed the government perceives it to be, but going ahead the market is going to get pretty huge,” he said.


This story has been published from a wire agency feed without modifications to the text. Only the headline has been changed.

Himax Solar Battery

There are certain specifications you should use when evaluating your solar battery options, such as how long the solar battery will last or how much power it can provide. Below, learn about all of the criteria that you should use to compare your home energy storage options, as well as the different types of solar batteries.

How to compare your solar storage options

As you consider your solar-plus-storage options, you’ll come across a lot of complicated product specifications. The most important ones to use during your evaluation are the battery’s capacity & power ratings, depth of discharge (DoD), round-trip efficiency, warranty, and manufacturer.

Capacity & power

Capacity is the total amount of electricity that a solar battery can store, measured in kilowatt-hours (kWh). Most home solar batteries are designed to be “stackable,” which means that you can include multiple batteries with your solar-plus-storage system to get extra capacity.

While capacity tells you how big your battery is, it doesn’t tell you how much electricity a battery can provide at a given moment. To get the full picture, you also need to consider the battery’s power rating. In the context of solar batteries, a power rating is the amount of electricity that a battery can deliver at one time. It is measured in kilowatts (kW).

A battery with a high capacity and a low power rating would deliver a low amount of electricity (enough to run a few crucial appliances) for a long time. A battery with low capacity and a high power rating could run your entire home, but only for a few hours.

Depth of discharge (DoD)

Most solar batteries need to retain some charge at all times due to their chemical composition. If you use 100 percent of a battery’s charge, its useful life will be significantly shortened.

The depth of discharge (DoD) of a battery refers to the amount of a battery’s capacity that has been used. Most manufacturers will specify a maximum DoD for optimal performance. For example, if a 10 kWh battery has a DoD of 90 percent, you shouldn’t use more than 9 kWh of the battery before recharging it. Generally speaking, a higher DoD means you will be able to utilize more of your battery’s capacity.

Himax Solar Battery

Round-trip efficiency

A battery’s round-trip efficiency represents the amount of energy that can be used as a percentage of the amount of energy that it took to store it. For example, if you feed five kWh of electricity into your battery and can only get four kWh of useful electricity back, the battery has 80 percent round-trip efficiency (4 kWh / 5 kWh = 80%). Generally speaking, a higher round-trip efficiency means you will get more economic value out of your battery.

Battery life & warranty

For most uses of home energy storage, your battery will “cycle” (charge and drain) daily. The battery’s ability to hold a charge will gradually decrease the more you use it. In this way, solar batteries are like the battery in your cell phone – you charge your phone each night to use it during the day, and as your phone gets older you’ll start to notice that the battery isn’t holding as much of a charge as it did when it was new. For example, a battery might be warrantied for 5,000 cycles or 10 years at 70 percent of its original capacity. This means that at the end of the warranty, the battery will have lost no more than 30 percent of its original ability to store energy.

Your solar battery will have a warranty that guarantees a certain number of cycles and/or years of useful life. Because battery performance naturally degrades over time, most manufacturers will also guarantee that the battery keeps a certain amount of its capacity over the course of the warranty. Therefore, the simple answer to the question “how long will my solar battery last?” is that it depends on the brand of battery you buy and and how much capacity it will lose over time.


Many different types of organizations are developing and manufacturing solar battery products, from automotive companies to tech startups. While a major automotive company entering the energy storage market likely has a longer history of product manufacturing, they may not offer the most revolutionary technology. By contrast, a tech startup might have a brand-new high-performing technology, but less of a track record to prove the battery’s long-term functionality.

Whether you choose a battery manufactured by a cutting-edge startup or a manufacturer with a long history depends on your priorities. Evaluating the warranties associated with each product can give you additional guidance as you make your decision.


How long do solar batteries last?

There are two ways to answer this question and the first is to determine how long a solar battery can power your home. In many cases, a fully charged battery can run your home overnight when your solar panels are not producing energy. To make a more exact calculation, you’ll need to know a few variables, including how much energy your household consumes in a given day, what the capacity and power rating is for your solar battery and whether or not you are connected to the electric grid.

For the sake of a simple example, we’ll determine the size of a battery needed to provide an adequate solar plus storage solution with national average data from the U.S. Energy Information Administration. The average U.S. household will use roughly 30 kilowatt-hours (kWh) of energy per day and a typical solar battery can deliver some 10 kWh of capacity. Thus a very simple answer would be, if you purchased three solar batteries, you could run your home for an entire day with nothing but battery support.

12V 100AH

In reality, the answer is more complicated than that. You will also be generating power with your solar panel system during the day which will offer strong power for some 6-7 hours of the day during peak sunlight hours. On the other end, most batteries cannot run at maximum capacity and generally peak at a 90% DoD (as explained above). As a result, your 10 kWh battery likely has a useful capacity of 9 kWh.

Ultimately, if you are pairing your battery with a solar PV array, one or two batteries can provide sufficient power during nighttime when your panels are not producing. However, without a renewable energy solution, you may need 3 batteries or more to power your entire home for 24 hours. Additionally, if you are installing home energy storage in order to disconnect from the electric grid, you should install a few days’ worth of backup power to account for days where you might have cloudy weather.


Solar battery lifespan

The general range for a solar battery’s useful lifespan is between 5 and 15 years. If you install a solar battery today, you will likely need to replace it at least once to match the 25 to 30 year lifespan of your PV system. However, just as the lifespan of solar panels has increased significantly in the past decade, it is expected that solar batteries will follow suit as the market for energy storage solutions grows.

Proper maintenance can also have a significant effect on your solar battery’s lifespan. Solar batteries are significantly impacted by temperature, so protecting your battery from freezing or sweltering temperatures can increase its useful life. When a PV battery drops below 30° F, it will require more voltage to reach maximum charge; when that same battery rises above the 90° F threshold, it will become overheated and require a reduction in charge. To solve this problem, many leading battery manufacturers, like Tesla, provide temperature moderation as a feature. However, if the battery that you buy does not, you will need to consider other solutions like earth-sheltered enclosures. Quality maintenance efforts can definitely impact how long your solar battery will last.


What are the best batteries for solar?

Batteries used in home energy storage typically are made with one of three chemical compositions: lead acid, lithium ion, and saltwater. In most cases, lithium ion batteries are the best option for a solar panel system, though other battery types can be more affordable.

1. Lead acid

Lead acid batteries are a tested technology that has been used in off-grid energy systems for decades. While they have a relatively short life and lower DoD than other battery types, they are also one of the least expensive options currently on the market in the home energy storage sector. For homeowners who want to go off the grid and need to install lots of energy storage, lead acid can be a good option.


2. Lithium ion

The majority of new home energy storage technologies, such as the , use some form of lithium ion chemical composition. Lithium ion batteries are lighter and more compact than lead acid batteries. They also have a higher DoD and longer lifespan when compared to lead acid batteries.  However, lithium ion batteries are more expensive than their lead acid counterparts.


3. Saltwater

A newcomer in the home energy storage industry is the saltwater battery. Unlike other home energy storage options, saltwater batteries don’t contain heavy metals, relying instead on saltwater electrolytes. While batteries that use heavy metals, including lead acid and lithium ion batteries, need to be disposed of with special processes, a saltwater battery can be easily recycled. However, as a new technology, saltwater batteries are relatively untested, and the one company that makes solar batteries for home use (Aquion) filed for bankruptcy in 2017.


  • Find the best solar battery for your home

51.2V 100Ah LiFePO4 Battery

12V 150Ah LiFePO4 Battery

12V 120Ah LiFePO4 Battery


lead-acid battery can be replaced by a lithium-ion battery

Batteries became an indispensable part of our daily lives during the 20th Century. But the pace of change has dramatically increased in the 21st Century with the development of new battery types. The resulting battery revolution that is underway is enabling the beginning of a seismic shift in the way we power our transportation systems and heavy equipment, as well as how we power our cities.

The key to this revolution has been the development of affordable batteries with much greater energy density. This new generation of batteries threatens to end the lengthy reign of the lead-acid battery.

But consumers could be forgiven for being confused about the many different battery types vying for market share in this exciting new future. So let’s break down the basics of battery types and their applications.

Battery Categories

Batteries are broadly categorized as either primary or secondary. A primary battery is a disposable battery. We are all familiar with those types of batteries. The most common type of primary battery is the alkaline battery, so named because its electrolyte is alkaline (potassium hydroxide).

The 20-pack of Duracell batteries you buy at the hardware store for $15 are alkaline batteries. These batteries come in different sizes and with different voltage levels, the most common of which are designated AA, AAA, C, D, and 9-volt.

Primary batteries are cheap, and are used in flashlights, TV remotes, toys, and consumer electronics.

Secondary batteries are rechargeable. The initial cost of these batteries is usually higher than with primary batteries, but they begin to have a significant economic advantage in power-hungry applications that would rapidly consume alkaline batteries.

Secondary Battery Types

The most common type of secondary battery is the lead-acid battery. The lead-acid battery is the oldest type of rechargeable battery, found in most of the world’s automobiles. It is relatively low-cost and reliable, but it has the lowest energy to volume and energy to weight ratio of the major types of secondary batteries. This makes it popular for energy storage applications in which weight and space aren’t a major concern — like backup power for solar photovoltaic systems. But for mobile applications that rely heavily on battery power, the lead-acid battery is being rapidly superseded by newer battery types.

The lithium-ion battery has emerged as the most serious contender for dethroning the lead-acid battery. Lithium-ion batteries are on the other end of the energy density scale from lead-acid batteries. They have the highest energy to volume and energy to weight ratio of the major types of secondary battery. That means you can pack more energy into a smaller space, and the weight will also be lower.

Lithium-ion batteries are still new compared to lead-acid batteries. The knock on them had been cost, but those costs have plummeted over the past decade, and are projected to continue declining.

The other two major types of secondary batteries are nickel-based, and both fall between lead-acid and lithium-ion in terms of energy density. The nickel–cadmium battery (Ni-Cd battery) uses nickel oxide hydroxide and metallic cadmium as electrodes. Ni-Cd batteries are great at maintaining voltage and holding charge when not in use. But these batteries are well-known for “memory” effects that take place when a partially charged battery is recharged. This degrades the capacity of the battery over time.

Ni-Cd batteries were once popular in portable power tools and portable electronic devices. But nickel-metal hydride (Ni-MH) batteries have largely supplanted them in these applications due to lower costs and higher energy density. In addition to having up to three times the capacity of a Ni-Cd battery of the same size, Ni-MH batteries don’t have the “memory” effect of Ni-Cd batteries.

Selecting the Right Battery

It can be difficult, given the increasing number of battery options, to determine the best type of battery for your application. Some important considerations are energy density, power density, cost, cycle life durability, voltage, and safety.

These considerations generally involve trade-offs. Ideally a battery would possess high energy and power density, and good durability — at a low price. In reality, consumers have had to pay a premium for batteries with greater energy density. But that is changing.

Research organization Bloomberg NEF reported that the volume-weighted average lithium-ion battery pack price (which includes the cell and the pack) fell 85% from 2010-18, reaching an average of $176/kWh. BloombergNEF further projects that prices will fall to $94/kWh by 2024 and $62/kWh by 2030. That would reflect a 95% price decline over the course of 20 years. In comparison, lead-acid battery packs are still around $150/kWh, and that’s 160 years after the lead-acid battery was invented.

Thus, it may not be long before the most energy dense battery is also the cheapest battery. That has enormous implications for the future of lead-acid batteries.

Another important consideration is a battery’s capacity. The capacity defines the run-time of the battery, which reflects the discharge current the battery can provide until it needs recharging.

The energy content of a battery is obtained by multiplying the battery capacity in ampere hours (Ah) by the voltage to obtain watt-hours (Wh). Two batteries can have the same Ah capacity, but if one has a higher voltage it will have more energy.

These are important concepts to understand if you are trying to decide on a battery to power a flashlight versus one to power a forklift.

The power density defines the maximum rate of discharge of the battery. Some batteries require a low rate of discharge, but those used to provide bursts of power will need greater power density.

As the battery is discharged, it will have to be recharged. The cycle life durability of a battery defines the stability of the battery through repeated cycles.

Finally, the operating environment of the battery needs to be considered. High or low temperatures, for example, can impact a battery’s performance and safety.

Case Study

Over the next few years, many companies are going to grapple with the decision of whether to transition their applications from lead-acid to more modern battery types. There are several economic considerations, which can be demonstrated with a case study.

Tim Karimov, who is the President at California-based lithium-ion battery supplier OneCharge, has said their customers show “the total cost of ownership for Li-ion averages 20% to 40% lower in just 2 to 4 years.”

Here is how they arrive at that number. While they don’t cite base capacity costs for lithium-ion batteries versus lead-acid batteries, they do note in a presentation that a lead-acid battery can be replaced by a lithium-ion battery with as little as 60% of the same capacity:

lead-acid battery can be replaced by a lithium-ion battery

Lead-acid to lithium-ion comparison ONECHARGE PRESENTATION

The reason for this is that the maximum discharge of the lead-acid batteries is 80%, whereas lithium-ion batteries can be discharged to zero. In addition to that, lithium-ion batteries can be charged at various points during the day (breaks, etc.), a practice that would quickly reduce the lifespan of the lead-acid battery.

For example, the company cites a recent case study in which a customer was able to reduce the number of lift trucks they had on hand from 17 to 12 by switching from lead-acid batteries to lithium-ion batteries — primarily because of opportunity charging.

Thus, even though the price for capacity is higher for lithium-ion batteries, the fact that you need less capacity lowers the lithium-ion premium (which, according to BloombergNEF, likely won’t be a premium for much longer).

Karimov cites additional savings from a case study from a fruit-growing, packaging and shipping operation with 2 shifts and 30 trucks:

  • Downtime from battery changes — $56,000 per year
  • Watering the lead acid batteries — $8,000 per year
  • The need for a new battery room — $440,000
  • Higher preventative maintenance costs and insurance rates related to health risks with lead acid

In addition, lithium-ion batteries have a longer life cycle with 3,000 cycles compared to less than 1,500 with lead acid. Historically, consumers considered such savings in deciding whether to switch to lithium-ion batteries. But with declining lithium-ion prices, that decision may soon be much easier.


The world is in the midst of a battery revolution, but declining costs and a rising installed base signal that lithium-ion batteries are set to displace lead-acid batteries. As long as lithium-ion batteries are more expensive than lead-acid batteries, the economics will depend on just how much the batteries are used (which impacts downtime, maintenance, etc.).

But as the price of lithium-ion continues to fall, the economic case will be compelling just on the price of the batteries. When that happens, the age of lead-acid batteries will come to an end.