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.

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

Life-cycle-of-a-ternary-lithium-battery

With the promotion of energy conservation and environmental protection, more and more environmentally friendly products are being applied to the market. In the battery industry, ternary lithium batteries with many advantages quickly occupied the market, and gradually replace the traditional lead-acid batteries. For the traditional battery, ternary lithium batteries have a long life, energy-saving and environmental protection without pollution, low maintenance costs, charge and discharge completely, lightweight, and so on, the total ternary lithium battery life, how long it will be?

What is a ternary lithium battery?

In nature, lithium is the lightest metal with the smallest atomic mass. Its atomic weight is 6.94g/mol and ρ=0.53g/cm3. Lithium is chemically active and easily loses electrons and is oxidized to Li+. Therefore, the standard electrode potential is the most negative, -3.045V, and the electrochemical equivalent is the smallest, 0.26g/Ah. These characteristics decide that it is a material with high specific energy. Ternary lithium battery refers to the lithium secondary battery that uses three transition metal oxides of nickel-cobalt-manganese as the cathode material. It fully integrates the good cycling performance of lithium cobaltate, the high specific capacity of lithium nickelate, and the high safety and low cost of lithium manganate, which synthesizes nickel-cobalt-manganese and other multi-element synergistic lithium-embedded oxide by molecular level mixing, doping, coating, and surface modification methods. The ternary lithium battery is a kind of lithium-ion rechargeable battery that is widely researched and applied at present.

The life of ternary lithium battery

The so-called lithium battery life refers to capacity decay of nominal capacity with a period of battery use ( at room temperature 25 ℃, standard atmospheric pressure, and discharge at 0.2C)

can be considered the end of life. In the industry, the cycle life is generally calculated by the number of cycles of full charge and discharge of lithium batteries. In the process of use, an irreversible electrochemical reaction occurs inside the lithium battery, which leads to a decrease in capacity, such as the decomposition of the electrolyte, the deactivation of active materials, the collapse of the positive and negative structures, and the reduction in the number of lithium ions inserted and extracted. Experiments have shown that a higher discharge rate will lead to a faster attenuation of capacity. If the discharge current is lower, the battery voltage will be close to the equilibrium voltage and more energy can be released.

Life of ternary lithium battery

The theoretical life of a ternary lithium battery is about 800 cycles, which is medium among commercially rechargeable lithium batteries. Lithium iron phosphate is about 2,000 cycles, while lithium titanate is said to reach 10,000 cycles. At present, mainstream battery manufacturers promise more than 500 times (charge and discharge under standard conditions) in the specifications of their ternary battery cells. Manufacturers recommend that the SOC use window is 10%~90%. Deep charging and discharging are not recommended, otherwise, it will cause irreversible damage to the positive and negative structure of the battery. If it is calculated by shallow charge and shallow discharge, the cycle life will be at least 1000 times. In addition, if the lithium battery is often discharged under high rate and high-temperature environment, the battery life will be greatly reduced to less than 200 times

The number of life cycles of lithium batteries is based on battery quality and battery materials.

  1. The cycle times of ternary materials are about 800 times.
  2. Lithium iron phosphate battery is cycled about 2500 times.

Grepow has long been manufacturing battery packs, ternary lithium batteries, lithium polymer batteries, lithium iron phosphate batteries, and so on. The product has a wide range of applications and high quality. Grepow is the world’s top battery manufacturer, which was founded in 1998, over 20 years of experience in battery manufacturing. There are currently 3 self-owned brands “格氏 ACE”, “GENS ACE” and “TATTU”.

In today’s lithium battery market, ternary lithium batteries are the most widely used. They are moderate in terms of performance and low in price. Therefore, the ternary lithium batteries are the most cost-effective.

Low-temperature lithium-ion batteries mainly include low-temperature lithium-ion polymer (LiPo) batteries, low-temperature 18650 batteries, and low-temperature lithium iron phosphate (LiPO4) batteries.  We will explore the advantages and disadvantages of each one.

Low-temperature lithium polymer batteries

Low-temperature LiPo batteries have the best low-temperature performance especially in smart wearable devices, where the advantages are more prominent.

Performance characteristics

Himax’s LiPo batteries can be made to operate in environments with low-temperatures of -50℃ to 50℃. Under low-temperatures, the batteries can achieve a lower internal resistance and, thus, a high discharge rate. Compared with traditional lithium polymer batteries, Himax’s batteries have broken through the discharge temperature limits of -20℃ to 60℃.

They are able to discharge over 60% efficiency at 0.2C at -40℃ and discharge over 80% efficiency at 0.2C at -30℃. When charged at 20℃ to 30℃ by 0.2C, the capacity can maintain above 85% after 300 cycles. The batteries can be ready for mass production, and they have been widely used in cold climates and military products.

Shape advantage

With stacking technology, battery shapes can be widely customized, which allows for more flexibility and space within products. We can also create small and ultra-thin batteries with low-temperature characteristics used in special fields or professional smart equipment.

Weight advantage

Under the same voltage and capacity conditions, low-temperature lithium-ion polymer batteries and low-temperature lithium iron phosphate batteries are lighter than low-temperature 18650 batteries. However, LiPo batteries are the most expensive in terms of production and manufacturing costs, which is one of the important factors limiting its use in some application areas.

 

Low-temperature 18650 lithium-ion batteries

Low-temperature 18650 lithium-ion batteries mainly consist of liquid electrolytes. these cylindrical batteries with steel shells have fixed dimensions, which means that their shape and size are fixed as well. The largest capacity is currently 3300mAh, which can only be achieved by a limited number of manufacturers.

Characteristics

At temperatures between -40℃ to 60℃, the effective discharge capacity is 40% to 55%, and the effective cycle life is more than 180 cycles.  At temperatures between -30℃ to 65℃ at 0.2C discharge, the effective discharge capacity is above 65%. At 1C rate discharge, the discharge capacity is above 60%, and the cycle life comes out to more than 200 cycles.

At temperatures between -20℃ to 75℃, the effective discharge capacity is more than 80%, and the cycle life is more than 300 cycles.

Due to the fixed performance and size of the battery, there is limited use for this battery, but its production and manufacturing costs are relatively low.

Low-temperature lithium iron phosphate batteries

Low-temperature LiPO4 batteries have two kinds of packaging cases

one is a steel case, which is currently mostly used in new energy batteries, such as energy-storage batteries and new energy vehicle batteries. The other is a soft-pack LiPO4 battery with aluminum plastic film for the outer packaging.

 

The performance of this battery is basically the same as that of the LiPo battery.

However, the low-temperature performance of LiPo batteries is better than that of 18650 batteries. The development of LiPO4-battery technology has not been long, and the requirements for production equipment are relatively high.

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)

Automotive-Fuel-Cells

Can “oiling” the electrodes of automotive fuel cells prevent their degradation?

Unlike their larger, utility-scale counterparts that run continuously, automotive fuel cells are frequently turned off and on, allowing electrodes to corrode during the off state due to unwanted chemical reactions. The introduction of a specialized catalyst is shown to contain the problem.

A research team at Pohang University of Science and Technology (POSTECH) employed a catalyst to solve corrosion in fuel cells occurring when hydrogen cars are shut down.

The catalyst, platinum-hydrogen tungsten bronze (Pt/HxWO3), has been demonstrated to promote hydrogen oxidation and selectively suppress oxygen reduction reactions (ORR).

For some chemical insight, W is the chemical symbol for tungsten, and Pt, H and O stand for platinum, hydrogen, and oxygen, respectively. HxWO3 is familiar to chemists as hydrogen tungsten bronze.

 

The Metal-Insulator Transition Phenomena

The project focused on the Metal-Insulator Transition (MIT) phenomenon, which can selectively change materials’ conductivity depending on the surrounding environment. In this study, insulator characteristics were obtained with high oxygen pressure and metal characteristics when hydrogen pressure is high.

Tungsten bronze changes conductivity through the insertion and removal of protons. When the fuel cell is operating, applying the MIT phenomenon of WO3 results in maintaining the H-WO3 conductor state with the insertion of a proton—when the fuel cell is off, mixed air is drawn in, increasing the oxygen pressure. This causes a change into WO3, which stops the unwanted electrode reaction, halting the cathode’s corrosion.

 

When the automotive fuel cell turns off and oxygen rushes in, the MIT Phenomena provides protection against electrode degradation.
When the automotive fuel cell turns off and oxygen rushes in, the MIT Phenomena provides protection against electrode degradation. Image credited to POSTECH

 

Results

The Pt/HxWO3 served as a selective hydrogen oxidation reaction (HOR) catalyst that was imparted by the metal-insulator transition phenomenon. It showed significant results for membrane electrode assemblies, which are defined as an aggregation of electrolytic membranes, anode electrodes, and cathodic poles.

Automotive fuel cells employing the demonstrated catalyst exhibit over twice the durability of conventional commercial Pt/C catalyst materials during fuel cell shut-down conditions.

Professor Yong-Tae Kim, who led the research, commented, “This research has dramatically improved automotive fuel cells’ durability.” He added, “It is anticipated that hydrogen cars’ commercialization may be further facilitated through these findings.”

 

Some Misconceptions About Hydrogen

Hydrogen may be the most abundant material in the universe, and it’s about number ten here on Earth. There are, literally, oceans of it – combined with oxygen to form water. To get the hydrogen gas, what’s used by fuel cells, energy has to be applied to water in electrolysis. Then you get hydrogen and oxygen gasses, which can then combine with oxygen to drive a fuel cell or launch a rocket into space.

In chemistry, as in life, nothing is free, and hydrogen gas is highly flammable.

Even if the thought of a teenage pump jockey at the local fill-up station causing a mini-apocalypse doesn’t fill you with terror, there are other disadvantages to using hydrogen as a fuel for vehicles.

 

The Hindenburg hydrogen balloon disaster.
The Hindenburg hydrogen balloon disaster. Image credited to the Smithsonian

 

Hydrogen’s Inefficiency

Let’s assume H2 gas is obtained from electrolysis powered by renewables. That process is 75% efficient. Then, H2 gas must be compressed, chilled, and transported to the hydrogen station. That process is about 90% efficient. Reconverting the hydrogen to electricity in the vehicle is 60% efficient. The motor driving the vehicle can be though to be 95% efficient.

 

Electric Vehicles

For Electric Vehicles (EV), you lose 5% in the power’s journey to the station, and another 10% for transferring energy to the battery and taking it out again to power the vehicle. The motor, as in the other case, loses 5%.

From 100 watts generated, a full 80 watts are available to move the vehicle. The image below illustrates the calculation. As noted in The Conversation, there are now about five million EVs on the road today, compared to a total of 7,500 hydrogen-powered vehicles. It’s not hard to see why.

As noted in The Conversation, there are now about five million EVs on the road today, compared to a total of 7,500 hydrogen-powered vehicles. It’s not hard to see why.

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:

  • 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.
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.”

Coulombic Efficiency: Research Gate

We seldom stress about buying a new phone every few years. We want the new technology. Hence with phones, lithium-ion battery aging is hardly an issue. It is, however, a major factor with an electric vehicle. Those lithium batteries can cost as much as a small fossil-fueled car pumping out pollution.

Lithium-Ion Battery Aging

Concept Electric Car: NREL: Public Domain

It follows that scientists are constantly on the prowl to retard lithium-ion battery aging. Although electric car batteries should last for twenty years, the design life of the vehicle is fifty.

Thus, it would be really nice if the batteries lasted as long. Researchers at Dalhousie University in Halifax think the answer lies in coulombic efficiency.

Coulombic Efficiency and Lithium-Ion Battery Aging

You can read about faradaic efficiency, faradaic yield, current efficiency, and coulombic efficiency here because they are all the same thing. In headline terms, they refer to the ability of a battery to sustain itself over time. We express this as a ratio using the formula Q-Out over Q-In. Q-out is the charge that exits the battery during discharge. Q-in is the amount of charge that enters it during charging. The result is inevitably less than one due to fundamental battery inefficiencies.

The Fundamental Inefficiency of Lithium Ion Batteries

Lithium-Ion Battery Aging

Lithium Research: Dept. of Energy: Public Domain

When we charge a lithium-ion battery, lithium moves across to the graphite, negative anode and lodges there. As we draw the current out, it theoretically all moves back to the cathode.

In practice, a small amount of lithium compound remains on the anode as a thin film. Every time we recharge the battery, this grows thicker. Eventually the lithium can no longer interact with the graphite.

Ongoing Research into Lithium-Ion Battery Aging

Scientists are on the hunt to retard the deterioration of lithium ion batteries. Some say this is the ‘holy grail’ of green energy. The key appears to be putting additives in the electrolyte. However nothing is perfect. Therefore a degree of lithium-ion battery aging will likely be with us forever.

NI-MH-Battery-Pack

NI-MH-Battery-Pack

Nickel metal hydride battery (Commonly abbreviated to “Nimh battery”) has dominated the market today. This is because the battery chemistry is advanced in performance, safety, the cycle of life, and other parameters. In addition to that, manufacturers are working to improve the cell. The cell is designed to be used on electronic products that consider run time. As a result of this, it is used in a wide range of applications. Before you buy a cell, it is essential to not some of the useful factors. Let us see safety, usage, and differences of nickel-metal hydride.

Are NiMh Batteries Safe?

Generally, batteries are safe to buy you need to take precautions. Nimh is a nontoxic cell to human beings but harmful to other living things such as plants. However, the main problem is electrolytes. When exposing to extreme temperatures, electrolytes react with materials to create gas.

How to Keep NiMh Battery Safe?

Proper Charging

Proper charging means fully charging a cell according to the manufacturer’s rule. You can determine the completely charged battery by examining charge currents as well as recording charge time. Moreover, you must charge a battery at a moderate temperature. Extreme temperatures can cause an internal circuit. This produces heat thus makes the cell to be unsafe. You can buy a battery charger that measures temperatures. It will alert you when the temperatures rise.

Proper Storage

Cells are not stored inside a device. Remove the battery from the equipment and put it in the original package. In addition to that, store it in a cool dry place to avoid heat. Also, cells should not be put in contact, ensure they are separated.

Ventilation

It is recommended to ventilate the room for charging cells. Electrolytes are produced during charging and they emit hydrogen. The gas colorless and odorless hence you cannot recognize. The downside of hydrogen is that it is highly explosive. It mixes with oxygen in the air when produced. Since hydrogen is lighter than oxygen, it accumulates above oxygen. For this reason, it can result in a massive explosion in the room. On top of that, hydrogen can cause eye and skin problems.

Easy Safety Tips To Follow

  • Cells should always keep devices away from children. This includes wrist watches, remote controls, thermometers, cards, and other products that have batteries.
  • Do not expose lose batteries to pets and small children. Keep them away from access.
  • Create awareness by teaching friends and parents on keeping cells away.
  • If your child has swallowed a cell, run to the hospital, and do not give the child anything to drink.

What are NiMh Batteries Used For?

Mobile Phones

Nickel metal hydride has a greater density. The cell is designed to be a slim geometry. This gives an energy density of about 60Wh/kg. The cell takes up to 300 life cycles. Ways to increase cycles include draining and recharging the device for about four times.

Laptops

Laptops use several types of cells including nickel-metal hydride. The batteries work well in portable computers and last longer, unlike nickel-cadmium. If you want to increase the life cycle of nickel-metal hydride on a laptop, you should discharge more often.

Computers

Computers that use NiMH last longer. Also, they deliver great performance.

Digital Cameras

A good digital camera should work for long before it drains. Before the introduction of lithium-ion, most digital cameras used Nimh and still use.

What is the Difference Between A NiMh Battery and A Lithium-ion Battery?

Charge Cycles

The charge cycle is referred to as the charging and discharging process of a rechargeable battery. The lithium-ion battery has a powerful ability to perform longer charge cycles compared to nickel-metal hydride. This parameter contributes to the high cost of lithium-ion batteries. There are ways you can do to increase life cycles. For example, reducing the battery temperature, choose the right termination charge, prevent high charge, and discharge.

Voltages

Voltage is the characteristic of a cell. It is examined through chemical reactions, polarization, and components of a battery. The nominal voltage of a lithium-ion is about 3.70V. On the contrary, nickel-metal hydride operates at a nominal voltage of 1.2V in each cell. A high nominal voltage is great because it increases watt-hours.

High Power

Lithium-ion battery operates at higher voltage hence it delivers more power compared to nickel-metal hydride. NiMH produces has lower voltages that can support high power.

Chargers

Nickel metal hydride and lithium-ion need specific chargers. These chargers have different types of electronics. You cannot use a different charger on li-ion because it can result in accidents. Manufacturers have designed chargers that show currents, voltages as well as charge time. Also, it examines the rate of charging and cuts the process in case of issues. Conversely, nickel-metal hydride chargers do not come with safety parameters.

Size

Lithium-ion is a more advanced cell with less weight than most battery technology. Nickel metal hydride is among the heavy cells. Weight is a crucial factor to consider when it comes to transportation. Lithium-ion can be moved from one place to another without using much energy.

Dangerous

Nickel metal hydride is not as dangerous as lithium-ion. Nickel metal hydride does not cause a fire when exposed to oxygen. Lithium-ion explodes when exposed to oxygen. Therefore, it requires a protection circuit to guarantee safety.

Price

The most important thing when you buy a cell is checking the price of a product. The cost of lithium-ion is almost three times s more of other batteries. Nickel metal hydride is affordable. The rise of demand for cells in consumer electronics will make the price of lithium to go down.

Top Nimh Battery Manufacturers Recommend

Himax was founded in 2002 and started to produce nickel-metal hydride batteries, and successfully developed high power and Low-self discharge NiMH batteries. Now Himax Nimh batteries are widely used in applications that require higher power, such as radio control cars, toys, power tools (e.g. electric drill, saws, angle grinders, etc.), and some medical devices in the global market.