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China’s CATL Poised To Overtake LG Chem As Top EV Battery Maker

EV-Battery-3.2v-100ah-200ah-280ah

EV-Battery-3.2v-100ah-200ah-280ah

Global competition for the world’s top spot for the manufacture of rechargeable batteries is getting fiercer as China is stepping up efforts to overtake its South Korean rival in the fast-growing electric vehicle market, Koreainvestors.com reports.

According to market research firm SNE Research on Oct. 5, South Korea’s LG Chem Ltd. maintained its market lead with 15.92 GWh of battery capacity supply in the first eight months of this year, accounting for 24.6% of the global EV battery market.

China’s Contemporary Amperex Technology Co. (CATL) came in second with 15.54 GWh, or 24% of the global market, followed by Japan’s Panasonic, whose market share stood at 19.2%.

Korea’s two other EV battery makers — Samsung SDI Co. and SK Innovation Co. — ranked fourth and sixth with 6.3% and 4.2%, respectively.

Data showed China’s CATL is swiftly closing in on market leader LG Chem. In July, LG Chem’s market share was 1.3 percentage points higher than CATL’s.

“LG Chem was able to keep its market leader position in the first half as the Chinese EV market shrank due to the coronavirus pandemic. But with the gradual recovery of the Chinese market since July, China’s battery makers are quickly narrowing the gap with their Korean rivals,” said a battery industry official.

Electric vehicles sold in China reached 83,000 units in August, more than half the global EV sales of 163,000 units.

China’s CATL poised to lead global market

CATL, which takes up 50-60% of the Chinese battery market, aims to expand its presence in Europe by building a plant in Germany and forging a partnership with Daimler AG.

Analysts said Chinese EV battery makers, on the back of strong government support, could overtake their Korean rivals in the near future. The Chinese government recently announced that it will extend state subsidies to its battery makers until the end of 2022. Such subsidies were scheduled to be phased out by the end of 2020.

Energy market researcher BloombergNEF predicts Chinese manufacturers will take the top spot in the global supply of EV batteries by the end of this year, leaving their Korean and Japanese rivals behind.

Korean companies are also facing competition from smaller rivals in Europe, where the growing EV market has helped LG Chem and other Korean battery makers gain ground in the global market.

Crowded EV battery market

According to foreign media reports, Northvolt AB, a Swedish battery developer and manufacturer, recently raised 600 million euros (820 billion won) in investment funding, in which German automaker Volkswagen also participated.

With the raised funds, Northvolt is known to be expanding its annual battery production capacity in Europe to 150 GWh by 2030.

Electric vehicle makers are also joining the race.

At its annual Battery Day on Sept. 22, Tesla Chief Executive Elon Musk said the company will make next-generation batteries for its electric cars in-house to cut costs.

The company said its battery production will rise to 100 GWh a year by 2022, similar to LG Chem’s annual output capacity for this year.

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Why Can’t The Maximum Voltage Of A Lithium-ion Battery Exceed 4.2V?

Lithium-Ion-Battery

The voltage of a lithium-ion battery is determined by the electrode potential. Voltage, also known as potential difference or potential difference, is a physical quantity that measures the energy difference of electric charges in an electrostatic field due to different potentials. The electrode potential of lithium-ion batteries is about 3V, and the voltage of lithium-ion batteries varies with different materials.

For example, a general lithium-ion battery has a nominal voltage of 3.7V and a full-charge voltage of 4.2V; a lithium iron phosphate battery has a nominal voltage of 3.2V and a full-charge voltage of 3.65V. In other words, the potential difference between the positive electrode and the negative electrode of a lithium-ion battery in practical use cannot exceed 4.2V, which is a requirement based on material and use safety.

Lithium-Ion-Battery

If the Li/Li+ electrode is used as the reference potential, μA is the relative electrochemical potential of the negative electrode material, μC is the relative electrochemical potential of the positive electrode material, and Eg, the electrolyte potential range, is the difference between the lowest electron unoccupied energy level and the highest electron occupied energy level. So the maximum voltage of the lithium-ion battery is determined by μA、μC、Eg.

The difference between μA and μC is the open-circuit voltage (the highest voltage value) of the lithium-ion battery. When this voltage value is in the Eg range, the normal operation of an electrolyte can be ensured. Normal operation means that the lithium-ion battery moves back and forth between the positive and negative electrodes through the electrolyte, but does not undergo oxidation-reduction reactions with the electrolyte, So as to ensure the stability of the battery structure. The electrochemical potential of the positive and negative materials causes the electrolyte to work abnormally in two forms:

  1. When the electrochemical potential of the negative electrode is higher than the lowest electron and unoccupied energy level of the electrolyte, the electrons of the negative electrode will be captured by the electrolyte, and the electrolyte will be oxidized, then the reaction product will form a solid-liquid interface layer on the surface of the negative electrode material particles. As a result, the negative electrode may be damaged.
  2. When the electrochemical potential of the positive electrode is lower than the highest electron-occupied energy level of the electrolyte, the electrons in the electrolyte will be captured by the positive electrode and oxidized by the electrolyte. Then the reaction product forms a solid-liquid interface layer on the surface of the positive electrode material particles, resulting in the positive electrode may be damaged.

However, the possibility of damage to the positive or negative electrode is due to the existence of the solid-liquid interface layer, which prevents the further movement of electrons between the electrolyte and the positive and negative electrodes, and instead protects the electrode material.

That is to say, the lighter solid The liquid interface layer is protective. The premise of this protection is that the electrochemical potential of the positive and negative electrodes can slightly exceed the Eg interval, but not too much.

For example, the reason why most of the current lithium-ion battery anode materials use graphite is that the electrochemical potential of graphite related to Li/Li+ electrodes is about 0.2V, which slightly exceeds the Eg range (1V~4.5V), but because of its protective properties, the solid-liquid interface layer prevents the electrolyte from being further reduced, thus stopping the continuous development of the polarization reaction.

However, the 5V high-voltage cathode material is far beyond the Eg range of the current commercial organic electrolyte, so it is easily oxidized during charging and discharging. With the increase of charging and discharging times, the capacity decreases and the service life also decreases.

The reason why the open-circuit voltage of the lithium-ion battery is selected to be 4.2V is that the Eg range of the electrolyte of the existing commercial lithium-ion battery is 1V ~ 4.5V. If the open-circuit voltage is set to 4.5V, the output power of the lithium-ion battery may be increased, but it also increases the risk of battery overcharge, and the harm of overcharge has been explained by a lot of data, so there is no additional explanation here.

If you are interested in battery products, please don’t hesitate to contact us at any time!
Email: sales@himaxelectronics.com

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How to Connect Batteries in Series and Parallel?

CONNECTING-BATTERIES-IN-SERIES---PARALLEL
Series - Parallel Connected Batteries

If you have ever worked with batteries you have probably come across the terms series, parallel, and series-parallel, but what exactly do these terms mean?

Series, Series-Parallel, and Parallel is the act of connecting two batteries together, but why would you want to connect two or more batteries together in the first place?

By connecting two or more batteries in either series, series-parallel, or parallel, you can increase the voltage or amp-hour capacity, or even both; allowing for higher voltage applications or power hungry applications.

Connecting Batteries In Series

Connecting a battery in series is when you connect two or more batteries together to increase the battery systems overall voltage, connecting batteries in series does not increase the capacity only the voltage.

For example if you connect four 12Volt 26Ah batteries you will have a battery voltage of 48Volts and battery capacity of 26Ah.

To configure batteries with a series connection each battery must have the same voltage and capacity rating, or you can potentially damage the batteries. For example you can connect two 6Volt 10Ah batteries together in series but you can not connect one 6V 10Ah battery with one 12V 10Ah battery.

To connect a group of batteries in series you connect the negative terminal of one battery to the positive terminal of another and so on until all batteries are connected, you would then connect a link/cable to the negative terminal of the first battery in your string of batteries to your application, then another cable to the positive terminal of the last battery in your string to your application.

When charging batteries in series, you need to use a charger that matches the battery system voltage. We recommend you charge each battery individually to avoid battery imbalance.

CONNECTING BATTERIES IN SERIES

Connecting Batteries In Parallel

Connecting a battery in parallel is when you connect two or more batteries together to increase the amp-hour capacity, with a parallel battery connection the capacity will increase, however the battery voltage will remain the same.

For example if you connect four 12V 100Ah batteries you would get a 12V 400Ah battery system.

When connecting batteries in parallel the negative terminal of one battery is connected to the negative terminal of the next and so on through the string of batteries, the same is done with positive terminals, ie positive terminal of one battery to the positive terminal of the next. For example if you needed a 12V 300Ah battery system you will need to connect three 12V 100Ah batteries together in parallel.

Parallel battery configuration helps increase the duration in which batteries can power equipment, but due to the increased amp-hour capacity they can take longer to charge than series connected batteries.

CONNECTING BATTERIES IN PARALLEL

Series – Parallel Connected Batteries

Last but not least! There is series-parallel connected batteries. Series-parallel connection is when you connect a string of batteries to increase both the voltage and capacity of the battery system.

For example you can connect six 6V 100Ah batteries together to give you a 24V 200Ah battery, this is achieved by configuring two strings of four In this connection you will have two or more sets of batteries which will be configured in both series and parallel to increase the system capacity.

If you need any help with configuring batteries in series, parallel or series parallel please get in contact with one of our battery experts. (Article cited: power-sonic.com)

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Battery Construction

12-volts-battery

The word battery simply means a group of similar components. In military vocabulary, a “battery” refers to a cluster of guns. In electricity, a “battery” is a set of voltaic cells designed to provide greater voltage and/or current than is possible with one cell alone.

The symbol for a cell is very simple, consisting of one long line and one short line, parallel to each other, with connecting wires:

cell

The symbol for a battery is nothing more than a couple of cell symbols stacked in series:

battery

As was stated before, the voltage produced by any particular kind of cell is determined strictly by the chemistry of that cell type. The size of the cell is irrelevant to its voltage. To obtain greater voltage than the output of a single cell, multiple cells must be connected in series. The total voltage of a battery is the sum of all cell voltages. A typical automotive lead-acid battery has six cells, for a nominal voltage output of 6 x 2.0 or 12.0 volts:

12 volts battery

The cells in an automotive battery are contained within the same hard rubber housing, connected together with thick, lead bars instead of wires. The electrodes and electrolyte solutions for each cell are contained in separate, partitioned sections of the battery case. In large batteries, the electrodes commonly take the shape of thin metal grids or plates and are often referred to as plates instead of electrodes.

For the sake of convenience, battery symbols are usually limited to four lines, alternating long/short, although the real battery it represents may have many more cells than that. On occasion, however, you might come across a symbol for a battery with unusually high voltage, intentionally drawn with extra lines. The lines, of course, are representative of the individual cell plates:

unusually high voltage symbol for battery

How is the Size of the Battery Relevant?

If the physical size of a cell has no impact on its voltage, then what does it affect? The answer is resistance, which in turn affects the maximum amount of current that a cell can provide. Every voltaic cell contains some amount of internal resistance due to the electrodes and the electrolyte. The larger a cell is constructed, the greater the electrode contact area with the electrolyte, and thus the less internal resistance it will have.

Although we generally consider a cell or battery in a circuit to be a perfect source of voltage (absolutely constant), the current through it dictated solely by the external resistance of the circuit to which it is attached, this is not entirely true in real life. Since every cell or battery contains some internal resistance, that resistance must affect the current in any given circuit:

ideal real battery 1

The real battery shown above within the dotted lines has an internal resistance of 0.2 Ω, which affects its ability to supply current to the load resistance of 1 Ω. The ideal battery on the left has no internal resistance, and so our Ohm’s Law calculations for current (I=E/R) give us a perfect value of 10 amps for current with the 1-ohm load and 10 volt supply. The real battery, with its built-in resistance, further impeding the flow of current, can only supply 8.333 amps to the same resistance load.

The ideal battery, in a short circuit with 0 Ω resistance, would be able to supply an infinite amount of current. The real battery, on the other hand, can only supply 50 amps (10 volts / 0.2 Ω) to a short circuit of 0 Ω resistance, due to its internal resistance. The chemical reaction inside the cell may still be providing exactly 10 volts, but the voltage is dropped across that internal resistance as current flows through the battery, which reduces the amount of voltage available at the battery terminals to the load.

How to Connect Cells to Minimize the Battery’s Internal Resistance?

Since we live in an imperfect world, with imperfect batteries, we need to understand the implications of factors such as internal resistance. Typically, batteries are placed in applications where their internal resistance is negligible compared to that of the circuit load (where their short-circuit current far exceeds their usual load current), and so the performance is very close to that of an ideal voltage source.

If we need to construct a battery with lower resistance than what one cell can provide (for greater current capacity), we will have to connect the cells together in parallel:

batterys internal resistance

Essentially, what we have done here is to determine the Thevenin equivalent of the five cells in parallel (an equivalent network of one voltage source and one series resistance). The equivalent network has the same source voltage but a fraction of the resistance of any individual cell in the original network. The overall effect of connecting cells in parallel is to decrease the equivalent internal resistance, just as resistors in parallel diminish in total resistance. The equivalent internal resistance of this battery of 5 cells is 1/5 that of each individual cell. The overall voltage stays the same: 2.0 volts. If this battery of cells were powering a circuit, the current through each cell would be 1/5 of the total circuit current, due to the equal split of current through equal-resistance parallel branches.

REVIEW:

  • A battery is a cluster of cells connected together for greater voltage and/or current capacity.
  • Cells connected together in series (polarities aiding) results in greater total voltage.
  • Physical cell size impacts cell resistance, which in turn impacts the ability for the cell to supply current to a circuit. Generally, the larger the cell, the less its internal resistance.
  • Cells connected together in parallel results in less total resistance, and potentially greater total current.
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Cracking the Code of a Scientific Anomaly: Decades-Old Mystery of Lithium-Ion Battery Storage Solved

Yu-Lab-Battery-Testing-System-scaled

 

Battery testing system in Dr. Yu’s Lab for developing advanced electrode materials. Credit: The University of Texas at Austin

For years, researchers have aimed to learn more about a group of metal oxides that show promise as key materials for the next generation of lithium-ion batteries because of their mysterious ability to store significantly more energy than should be possible. An international research team, co-led by The University of Texas at Austin, has cracked the code of this scientific anomaly, knocking down a barrier to building ultra-fast battery energy storage systems.

The team found that these metal oxides possess unique ways to store energy beyond classic electrochemical storage mechanisms. The research, published in Nature Materials, found several types of metal compounds with up to three times the energy storage capability compared with materials common in today’s commercially available lithium-ion batteries.

Yu Lab Battery Testing System

By decoding this mystery, the researchers are helping unlock batteries with greater energy capacity. That could mean smaller, more powerful batteries able to rapidly deliver charges for everything from smartphones to electric vehicles.

“For nearly two decades, the research community has been perplexed by these materials’ anomalously high capacities beyond their theoretical limits,” said Guihua Yu, an associate professor in the Walker Department of Mechanical Engineering at the Cockrell School of Engineering and one of the leaders of the project. “This work demonstrates the very first experimental evidence to show the extra charge is stored physically inside these materials via space charge storage mechanism.”

To demonstrate this phenomenon, the team found a way to monitor and measure how the elements change over time. Researchers from UT, the Massachusetts Institute of Technology, the University of Waterloo in Canada, Shandong University of China, Qingdao University in China and the Chinese Academy of Sciences participated in the project.

At the center of the discovery are transition-metal oxides, which are compounds that include oxygen bonded with transition metals such as iron, nickel and zinc. Energy can be stored inside the metal oxides — as opposed to typical methods that see lithium ions move in and out of these materials or convert their crystal structures for energy storage. And the researchers show that additional charge capacity can also be stored at the surface of iron nanoparticles formed during a series of conventional electrochemical processes.

Yu Advanced Electrode Material Lab

A broad range of transition metals can unlock this extra capacity, according to the research, and they share a common thread — the ability to collect a high density of electrons. These materials aren’t yet ready for prime time, Yu said, primarily because of a lack of knowledge about them. But the researchers said these new findings should go a long way in shedding light on the potential of these materials.

The key technique employed in this study, named in situ magnetometry, is a real-time magnetic monitoring method to investigate the evolution of a material’s internal electronic structure. It is able to quantify the charge capacity by measuring variations in magnetism. This technique can be used to study charge storage at a very small scale that is beyond the capabilities of many conventional characterization tools.

“The most significant results were obtained from a technique commonly used by physicists but very rarely in the battery community,” Yu said. “This is a perfect showcase of a beautiful marriage of physics and electrochemistry.”

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UPS Backup Battery

UPS-Backup-Battery

Power failures do occur at times in our places of residents, businesses, and workplaces. This power failure can last for an extended period. And as we know, without electricity, all our work or pleasure will stop. Therefore, there is the need to have backup systems so that our work is protected from damage or data loss.

Also, backup systems help us minimize the financial loss caused by blackouts, low voltages, and other power supply problems.

Therefore, let us learn one excellent backup system known as an Uninterruptible power supply (UPS).

UPS-Backup-Battery

What is the UPS Backup Battery?

An Uninterruptible power supply (UPS) is also known as a battery backup, is an electronic device that provides emergency power when your regular power supply fails. UPS provides instant protection from input power interruptions by giving out the stored energy in batteries, robust capacitors, and flywheels.

Instant loss of power and power surges are two leading causes of damage to your devices. Thus, UPS protects hardware components of machines such as computers, data centers, telecommunication equipment, and all other electrical equipment. Power disruption can cause damage, fatalities, severe business disruption, or data loss.

UPS comes in different sizes, ranging from those meant to protect one computer without a monitor to those large units used to power entire data centers or buildings. Cheap power strips can protect your electrical devices but do not offer protection against drops in voltage, brownouts, blackouts, and other power supply problems.

Let us take, for instance; you are dealing with a project at home on your laptop with it plugged into an appropriate surge protection strip. You are busy with your work, and then suddenly, there is a power blackout. Although all the devices go off, your work won’t be interrupted since the laptop has a battery. This offers time to save your work then shut down your computer.

But for desktop computers, it is a different case. If you worked on your project on a desktop computer during the outage, then the system goes off when power is interrupted. This leads to loss of unsaved work and also gives your computer a lot of stress. UPS now plays its role here. It offers a window of time to save your work then shut the computer down in the right way.

You can also work for the entire period of interruption using the power stored in the UPS. Even in your absence, many UPS units come with software that enables them to detect a power outage and enables the computer to shut down automatically.

Main Types Of UPS Units

There are three main types of UPS units, namely:

A standby UPS unit – This type of battery backup charges its battery and then waits for the main power to be interrupted. When there is a power outage, the Standby UPS switches to the battery backup. It can support the device for a period of between 20-100 milliseconds, which is within the acceptable tolerance threshold.

A Line-Interactive UPS unit has the same design as a standby UPS unit, but a special transformer is included. This particular transformer makes this type of UPS better in dealing with brownouts and power surges. If you are residing in an area frequently affected by brownouts, this is the device to purchase.

An online UPS unit – this is the most expensive type of UPS. It completely separates the device attached to it from the wall power. There is never a single millisecond of power interruption with this backup system when there is power loss. The device is effectively an electronic firewall between your devices and the world, scrubbing and stabilizing all the electricity your devices are exposed to.

Can UPS Work Without the Battery?

UPS works mostly on batteries. Most UPS runs on batteries, and they cannot operate on dead or missing batteries. But in case you have the one that runs without batteries, then you will get the same voltage regulation and surge as you will be working with batteries.

Without batteries, the UPS will offer minimal protection, and even only the UPS’s surge side will work. You will not get line conditioning without a well-functioning battery. It is good to always have healthy batteries in your UPS for maximum protection of your hardware devices.

How do You Pick the Right UPS Backup Battery?

Picking the right battery for your home or device is always crucial. But these are the factors to consider when purchasing a UPS battery;

Durability

When choosing your UPS batteries, you should consider the batteries that can last for an extended period. Batteries that last for a short period are costly because you will require frequent replacements of your battery.

Size

Know the size of the battery that your UPS backup system requires. Do not purchase before checking because you can end up purchasing over-sized or under-sized batteries.

Appliances To Be Protected

It is always excellent to know the number and size of the appliances you want to protect using your UPS. If you are using the UPS in your computer, only then pick the small units UPS, but if used to support the entire building or home, you will need to have UPS with higher units.

Cost

Cost always plays a crucial role in the purchase of any product. It is good to purchase batteries that will not affect your budget. But the price should not be considered so much that the quality is left out. What benefit will you get if you purchase a battery at a lower price but dies after a few days? You will get a significant loss from cheaper batteries.

Type Of UPS

There are three main types of UPS discussed above. They have different power consumption rates. Therefore, it is good to know the type of UPS’s power consumption rate that you are currently using.

Conclusion

It is said that preventing an accident before it happens is wise. Therefore, it is crucial to protect your devices before becoming a victim of damages or data loss. Install a UPS in your workplace, home, or business, and get the best results. Always ensure that your UPS has healthy and working batteries. (Article cited: large.net)

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The Best LiFePo4 Battery For Solar Street Light

LiFePo4 battery for solar street light

LiFePo4 battery for solar street light

Lithium battery VS Lead-Acid

LiFePO4 Battery VS Lead-acid Battery

Flexibility

Durability

Accessibility

Efficiency

Why do we recommend LiFePO4 (LFP) batteries for solar street light?

Lithium iron battery parameters

The systems using AGM batteries require replacement once a year to ensure reliability. Generally, the labor cost of replacing AGM batteries exceeds the cost of the product itself, especially in Australia, Europe, North America and other places. The risks and hazards of frequent battery replacement cannot be ignored.

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How Can LiFePO4 Batteries Be Used To Replace Lead-acid?

12v-lifepo4-battery

Most energy storage systems, like UPS and solar energy storage, use lead-acid batteries,  but more and more people are coming to use lithium iron phosphate batteries (LiFePO4) instead.

How does LiFePO4 replace Lead-acid batteries?

LiFePO4 batteries are compatible with lead-acid-battery equipment all the while having a higher discharge platform, volumetric specific capacity, and cycle life.

12.8V-7Ah-Lead-acid-battery

12.8V 7Ah Lead-acid battery

The nominal voltage of each cell of a lead-acid battery is 2.1V while the LiFePO4 is 3.2V.

To connect cells in series to form a 12V battery pack, lithium iron phosphate only needs 4 cells (3.2V x 4 = 12.8V) compared to the 6 cells of a lead-acid battery (2.1V x 6 = 12.6V).  Already based on this knowledge, it is clear that lithium iron phosphate batteries are more advantageous than lead-acid batteries in terms of energy ratio, weight, and volume.

12V-7Ah Lithium Battery

12.8V 7Ah Himax LiFePO4 modular battery

Each LiFePO4 Modular 12.8V battery can be set up in parallel or series in order to meet the needs of your current set up. For example, for a 48V setup, 4 cells of 12V should be hooked up in series. Simply remove the Lead-Acid Batteries and replace them with the Lithium iron phosphate Batteries and attach cables and secure the holding bracket.

Limitation of Lead-acid batteries

The charging efficiency of Lead-acid batteries is relatively low at 70% whereas the charging efficiency of LiFePo4 batteries can exceed 80% or even 90%. A lead-acid battery needs more energy for recharging, so a lot of energy is lost during the charging process.

Some other features of lead-acid batteries are as follows:

  • Fast or partial charges ruin a lead-acid battery
  • Charging times are long from 6 to 8 hours
  • An incorrect charger or setting reduces battery life
  • Poor maintenance will also reduce battery life

Other benefits of Lead-acid replacement batteries

Consistent voltage for a longer time

No more flickering lights or spotty performance. Lead-acid batteries can be unreliable for powering accessories at 50% or lower whereas Himax 12.8V LiFePO4 Lead-acid replacement batteries provide a constant output of energy all the way down to as little as 5% of its power.

lead-acid-vs-LiFePO4-battery

Fast Charging

Lithium-ion batteries can be “fast” charged to 100% of their capacity. Normally, the LiFePo4 battery can be charged to 50% of its capacity in only 30 minutes. However, the Grepow lithium batteries with fast-charging technology can reach 100% of its capacity within 30 minutes; the maximum charging efficiency can go up to 3C for the charging rate.

Smart and Multi-connected battery

LiFePO4 batteries are equipped with a Battery Management System (BMS) board, and you can check on the State of Charge (SOC). More importantly, the 12.8V modular LiFePo4 battery allows for multiple connections, so you can connect batteries in series and parallel without an external BMS (max 4S10P; the maximum parameter is 51.2V and 70Ah). You can also assemble the battery into different structures and shapes to fit it into the available space of your device.

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How To Increases Battery Charging Rate?

According to the Physorg website, researchers at Northwestern University have developed an electrode for lithium-ion batteries that allows the battery to retain 10 times more power than the prior art, and the battery with the new electrode can be fast charging, increasing by 10 Double rates.

Battery capacity and fast charging are two major battery limitations. The capacity is limited by the charge density, which is how much lithium ions the two poles of the battery can hold. Fast charging is limited by the rate at which lithium ions reach the negative electrode from the electrolyte.

Fast-charging

The negative electrode of the existing lithium battery is formed by stacking a carbon-based graphene sheet layer, and one lithium atom needs to be adapted to 6 carbon atoms. In order to increase the amount of electricity stored, scientists have tried to use silicon instead of carbon so that silicon can be adapted to more lithium, reaching 4 lithium atoms corresponding to 1 silicon atom.

However, silicon can significantly expand and shrink during charging, causing rapid breakdown and loss of charge capacity. The shape of the graphene sheet also limits the charging rate of the battery. Although they are only one carbon atom thick, they are very long. Since it takes a long time for lithium to move into the middle of the graphene sheet, the phenomenon of ion “traffic jam” occurs at the edge of the graphene sheet.

Now, the research team has solved the above problems by combining two technologies. First, in order to stabilize the silicon to maintain the maximum charge capacity, they added silicon clusters between the graphene sheets, and the elasticity of the graphene sheets was used to match the change in the number of silicon atoms in the battery, so that a large number of lithium atoms were stored in the electrodes. The addition of silicon clusters allows for higher energy densities and also reduces the loss of charge capacity due to silicon expansion and shrinkage, which is the best of both worlds.

The chemical oxidation process is used to fabricate micropores from 10 nm to 20 nm on graphene sheets, which are called “face defects”, so lithium ions will reach the negative electrode along with this shortcut and will be stored in the negative electrode by reacting with silicon. This will reduce the battery charging time by a factor of 10.

The new technology can extend the charging life of lithium-ion batteries by 10 times. Even after 150 cycles of charging and discharging, the battery energy efficiency is still five times that of lithium-ion batteries on the existing market. And the technology is expected to enter the market in the next three to five years.

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8 Advantages of LiFePo4 Battery

Himax LiFepo4-battery-pack

The positive electrode of lithium-ion batteries is lithium iron phosphate material, which has great advantages in safety performance and cycle life. These are one of the most important technical indicators of power battery. Lifepo4 battery with 1C charging and discharging cycle life can be achieved 2000 times, the puncture does not explode, it is not easy to burn and explode when overcharged. Lithium iron phosphate cathode materials make large-capacity lithium-ion batteries easier to use in series.

Lithium iron phosphate as cathode material

Lifepo4 battery refers to a lithium-ion battery using lithium iron phosphate as a positive electrode material. The positive electrode materials of lithium-ion batteries mainly include lithium cobaltate, lithium manganate, lithium nickelate, ternary materials, lithium iron phosphate, and the like. Among them, lithium cobaltate is the positive electrode material used in most lithium-ion batteries. In principle, lithium iron phosphate is also an embedding and deintercalation process. This principle is identical to lithium cobaltate and lithium manganate.

 lifepo4 battery advantages

1. High charging and discharging efficiency

Lifepo4 battery is a lithium-ion secondary battery. One main purpose is for power batteries. It has great advantages over NI-MH and Ni-Cd batteries. Lifepo4 battery has high charge and discharges efficiency, and the charge and discharge efficiency can reach over 90% under the condition of discharge, while the lead-acid battery is about 80%.

2. lifepo4 battery high safety performance

The P-O bond in the lithium iron phosphate crystal is stable and difficult to decompose, and does not collapse or heat like a lithium cobaltate or form a strong oxidizing substance even at a high temperature or overcharge, and thus has good safety.

It has been reported that in the actual operation, a small part of the sample was found to have a burning phenomenon in the acupuncture or short-circuit test, but there was no explosion event. In the overcharge experiment, a high-voltage charge that was several times higher than the self-discharge voltage was used, and it was found that there was still an Explosion phenomenon. Nevertheless, its overcharge safety has been greatly improved compared to the ordinary liquid electrolyte lithium cobalt oxide battery.

3. Lifepo4 battery long cycle life

Lifepo4 battery refers to a lithium-ion battery using lithium iron phosphate as a positive electrode material.

The long-life lead-acid battery has a cycle life of about 300 times, and the highest is 500 times. The lithium iron phosphate power battery has a cycle life of more than 2000 times, and the standard charge (5-hour rate) can be used up to 2000 times.

The same quality lead-acid battery is “new half-year, old half-year, maintenance and maintenance for half a year”, up to 1~1.5 years, and the lifepo4 battery is used under the same conditions, the theoretical life will reach 7~8 years.

Considering comprehensively, the performance price ratio is theoretically more than four times that of lead-acid batteries. High-current discharge can be quickly charged and discharged with high current 2C. Under the special charger, the battery can be fully charged within 1.5 minutes of 1.5C charging, and the starting current can reach 2C, but the lead-acid battery has no such performance.

LiFepo4-battery-pack

4. Good temperature performance

The peak temperature of lithium iron phosphate can reach 350 ° C -500 ° C while lithium manganate and lithium cobaltate are only around 200 ° C. Wide operating temperature range (-20C–+75C), with high-temperature resistance, lithium iron phosphate electric heating peak can reach 350 °C-500 °C, while lithium manganate and lithium cobalt oxide only at 200 °C.

5. Lifepo4 battery High capacity

It has a larger capacity than ordinary batteries (lead-acid, etc.). The monomer capacity is 5AH-1000AH.

6. No memory effect

Rechargeable batteries work under conditions that are often not fully discharged, and the capacity will quickly fall below the rated capacity. This phenomenon is called the memory effect. Memory like nickel-metal hydride and nickel-cadmium batteries, but the lifepo4 battery does not have this phenomenon, no matter what state the battery is in, it can be used with the charge, no need to discharge and recharge.

3.2v-100ah-lifepo4-battery

7. Lightweight of lifepo4 battery

The lifepo4 battery of the same specification capacity is 2/3 of the volume of the lead-acid battery, and the weight is 1/3 of the lead-acid battery.

8. Lifepo4 batteries are environmentally friendly

The battery is generally considered to be free of any heavy metals and rare metals (Ni-MH batteries require rare metals), non-toxic (SGS certified), non-polluting, in line with European RoHS regulations, is an absolute green battery certificate.

Therefore, the reason why lithium batteries are favored by the industry is mainly environmental considerations. Therefore, the battery has been included in the “863” national high-tech development plan during the “Tenth Five-Year Plan” period and has become national key support and encouragement development project.

With China’s accession to the WTO, the export volume of electric bicycles in China will increase rapidly, and electric bicycles entering Europe and the United States have been required to be equipped with non-polluting batteries.

The performance of the lithium-ion battery depends mainly on the positive and negative materials. Lithium iron phosphate is a lithium battery material that has only appeared in recent years. Its safety performance and cycle life are incomparable to other materials. The most important technical indicators of the battery.

Lifepo4 battery has the advantages of non-toxic, non-polluting, good safety performance, a wide range of raw materials, low prices, and long life. It is an ideal cathode material for a new generation of lithium-ion batteries.