Achieve ultra-fast charging lithium ion batteries

A few days ago, Toshiba materials exhibited a negative material using tungsten oxide(WO3) to achieve ultra-fast charging lithium ion batteries. It is reported that because it can achieve high current input and output, the battery application range from energy recovery applications such as automobiles and construction machinery to high-current power supply applications with a wide range of coverage.

The characteristic of the battery is that the power density and energy density can be increased to 2 to 3 times that of the double capacitor(EDLC). Compared with lithium ion capacitors designed to increase the EDLC energy density, the energy density has also been improved.

Lithium-ion secondary batteries made of tungsten oxide as a negative electrode material can achieve ultra-high speed charging and discharging

In the area of EDLC, Li ion secondary batteries are not suitable for high-output applications due to insufficient output power and difficult development, and the development of this battery will make it possible to use batteries in high-output power applications.

What was developed was a powder material called WO2.72, which was obtained under WO3 oxygen deficiency to enhance electron conductivity. Due to the small internal resistance and excellent diffusion of Li ions, the material can be used as a negative electrode to achieve high current charging and discharging. In particular, the discharge characteristics at low temperatures are excellent, and even at -40 °C, they still have rate characteristics equal to or higher than EDLC discharge characteristics. Prior to this, the rate characteristics of Li ion secondary batteries and Li ion capacitors at low temperatures have been unresolved issues.

A 1 Ah sample battery was displayed on the Toshiba stand and a feature interpretation panel was added. As Toshiba Materials, they aim to supply the product as battery material to battery manufacturers.

Characteristic Description Panel for Electric Storage Devices Using Tungsten Oxide

1, Lithium battery weight light volume Lithium battery electric vehicle brand diversification, in terms of power performance is similar to lead-acid batteries, charging for 6 to 8 hours, according to the battery capacity can run 30 to 45 kilometers, weight only about 1/5 of lead-acid batteries. And at present, lithium batteries are guaranteed for 2 years and lead-acid batteries for 1 year.

2,Lithium batteries have non-activation characteristics Lithium batteries are easily activated. As long as the battery is activated after 3-5 normal charge and discharge cycles, the battery can be activated and the normal capacity can be restored. Due to the characteristics of the lithium battery itself, it is determined that it has almost no memory effect. Therefore, the user's new lithium battery does not require special methods and equipment during the activation process.

3, the lithium battery with memory effect in the lead acid battery, nickel battery charging, has been worried about the battery memory effect, and the electric bicycle lithium battery without memory effect, can be safely charged without worrying about the battery before the charging of electricity.

4, Lithium battery cycle life Long Lithium-ion battery charge and discharge at 1C times rate, its cycle life is greater than or equal to 500 times, 500 times the capacity, greater than the nominal copper beam 70 %. The lead-acid battery, even if discharged at 0.5, charges at 0.15 C, has a cycle life of less than or equal to 350 times and a capacity of less than or equal to 60 %.

5, wide operating temperature range Electric bicycle lithium-ion battery can work in the range of -25 degrees to 55 degrees, its capacitance can reach 70 % of the nominal capacity, while lead-acid battery can only work in the range of 10 degrees to 40 degrees, at -25 degrees Can not work normally.

6, Lithium battery charging time is short, green environmental protection because the electric bicycle lithium-ion battery has the characteristics of high current charging, so the charging time is only 4-5 hours, while the lead-acid battery takes 8 to 10 hours. There is no heavy metal lead that is harmful to the environment and it is a highly environmentally friendly product.

1,Batteries that are below the average wholesale price in the market will not be bought.

2, did not pass the market test for more than 2 years.

3, no electric car manufacturers with car batteries firmly do not buy.

4, high-priced batteries, if not produced by a large factory, resolutely do not buy.

5,Batteries that change the size of national standards will never be bought.

6, 5A discharge, 30 seconds at a voltage higher than 12.68 V determined not to buy, more than 90 % are short-lived batteries.

How long to use: How many years can a lithium-ion battery in an electric car use? I believe that most consumers have heard that the life span of lithium batteries is "500 times" and 500 times of charge and discharge. After this number, the battery is "dead". Many friends are able to extend the life of the battery every time. When the battery is completely exhausted, it will be charged. Does this really extend the battery's life? The answer is no. The life of a lithium battery is "500 times", not the number of charges, but a cycle of charging and discharging.

A charging cycle means that all the power of the battery is used from full to empty, and then filled from empty to full. This is not the same as a charge. For example, a lithium battery uses only half the electricity on the first day and then charges it slowly. If the next day is the same, that is, half of the charge, a total of two charges down, this can only count as one charging cycle, not two. Therefore, it may usually take several charges to complete a cycle. Each time a cycle is completed, the battery capacity is reduced a little.

However, this less power is very small, and high-quality batteries will still retain 80 % of their original capacity after multiple cycles. Many lithium power supply products are still in use after two or three years. Of course, lithium power life after the end is still need to be replaced. The so-called 500 times means that the manufacturer has achieved about 625 refillable times at a constant discharge depth, reaching 500 charging cycles. Due to the various effects of actual life, especially the discharge depth when charging, the "500 charging cycle" can only be used as a reference battery life.

Myth: We often have the mistake of "charging lithium batteries after they run out of power" or "continuing to rush after lithium batteries are full, and must be charged for 12 hours". It is not known that if you make lithium batteries overcharge or discharge, not only can the lithium battery life of electric vehicles be prolonged, but it will be shortened. So how to use lithium batteries properly?

1,Even if your lithium-ion battery can be charged for two to three days at a time, it is recommended that you charge it every day. Because the lithium battery after use is in a shallow cycle, charging every day will increase the life of the lithium battery of the electric car.

2, timely charging

Because the lithium battery will enter the vulcanization process after discharge, if it is charged in time, it can remove the non-serious vulcanization. Therefore, after the lithium battery is used, it must be charged as soon as possible, so that the battery power is full as far as possible.

3, regular deep discharge

The periodic deep discharge of the battery also facilitates the "activation" of the battery, which can slightly increase the battery capacity. The general method is to perform a complete discharge of the battery at regular intervals.

4, use the original charger as much as possible

In general, do not change the charger at will when you are not sure. In addition, do not remove the speed limit of the controller. After removing the speed limit of the controller, although it can increase the speed of some cars, it will reduce the service life of the battery.

5, lithium battery storage

When the battery is not used for a long time, the battery should be disconnected from the vehicle and the battery should be replenished with some electricity at intervals to avoid battery self-discharge or protect the power of the plate to over-discharge the battery.

The page contains the contents of the machine translation.