Fast charge car battery - the key to electric vehicle range

What is fast charge car battery?

Fast charge car battery is a battery with high charging rate, high energy density and high power density. This kind of battery can be quickly charged and recharged at any place and at any temperature.

At the same time, it is necessary to ensure that the battery can achieve the specified cycle life, related safety performance and electrical performance, so as to meet the requirements of long-distance driving of electric vehicles.

Now, the main fast charge car battery is a ternary lithium battery. Due to its higher energy density, its battery life is also better than that of lithium iron phosphate batteries of the same volume.

Moreover, this type of battery also has a higher upper limit of fast charging, so the energy replenishment efficiency is also higher than that of lithium iron phosphate batteries.

It is worth mentioning that the ternary lithium battery is more resistant to low temperature, so its battery life shrinks in winter, and it is far better than the lithium iron phosphate battery.

Why fast charge car battery is needed?

Battery life and charging issues have become important factors hindering the rapid popularization of electric vehicles.

Although the current battery life of pure electric vehicles exceeds 400 kilometers, which is enough to meet daily travel needs, it is really not suitable for long-distance driving, and the charging time is very slow. The normal charging time is about 8 hours.

Alleviate “charging anxiety” and improve user experience. Super fast charging has become an important direction for many car companies to compete in differentiated competition.

At present, car companies and battery manufacturers are promoting the charging rate upgrade from 1C-2C to 4C-6C, and the corresponding SOC30%-80% charging time is reduced from 15min-30min to 5min-7.5min. Electric vehicles are entering the era of super fast charging.

As the core component of electric vehicles, the battery pack’s performance under high-power charging conditions will directly determine whether super fast charging can be realized.

Two types of fast charge car batteries introduction

Battery fast charging technology, as a key breakthrough to solve the convenience of electric vehicle charging, has also become the core competitiveness of power battery companies to participate in future market competition, and is rapidly iteratively innovating.

For power battery super fast charging technology, some manufacturers of top 10 lithium ion battery manufacturers have given their targeted innovative solutions:
CATL
The fast charging effect of CATL fast charge car battery will be achieved. It takes less than 10 minutes to charge and the battery life exceeds 400 kilometers.

The CATL 4C qilin battery has the characteristics of multi-functional elastic interlayer, large surface cooling of the battery cell, and space sharing at the bottom, so it can well support fast charging.

The five major technical paths of fast charge car battery research in CATL:

● One is to improve the charging capacity of the negative electrode. The main method is to increase the surface active sites of the negative electrode material, reduce the lithium intercalation path, and increase the lithium intercalation rate.

● The second is to reduce the impedance of the SEI film. The main method is to develop an ultra-thin SEI film to reduce the migration path and impedance of lithium ions, while improving low temperature tolerance.

● The third is to increase the transmission rate of lithium ions in the liquid phase, mainly through fast-charging electrolytes to increase the transmission rate of lithium ions in the liquid phase.

● The fourth is to improve the temperature rise. The main method is to build a high-speed lithium ion transmission and superelectronic network on the positive electrode to reduce polarization and temperature rise.

● The fifth is to increase the lithium ion transmission rate in the diaphragm, mainly through the low tortuosity pores to improve the lithium ion liquid phase transmission rate.

Greater Bay Technology
Greater Bay Technology Phoenix battery integrates the latest scientific and technological innovation achievements of Greater Bay Technology in the fields of materials, electrochemistry, structure and control, so that electric vehicles have:
● Ability to function as usual in all weather (high and low temperature) conditions;

● It can achieve the highest 8C super fast charging (0-80% charging only takes 6 minutes) on different voltage platforms from 300 to 1000 volts;

● It also has leading comprehensive advantages in terms of safety, service life, specific energy, battery life and cost, and is not afraid to compete with fuel vehicles;

The advent of Greater Bay Technology Phoenix battery has raised the technical level of power battery and system to a new stage.

Difficulties that fast charge car battery needs to break through

1) There is still no reliable on-board method to detect battery aging (such as lithium precipitation and mechanical rupture).

2) Many new electrode materials have good fast charging ability, but their stability, decay mechanism, large-scale production and cost are still to be discussed.

3) At present, there are few researches on fast charging optimization strategies at low temperature, and these researches are crucial for the popularization and application of electric vehicles in cold regions.

4) In order to further optimize the charging process of the single battery in the battery pack and avoid local aging or overcharging, an advanced BMS system with balanced battery consistency needs to be developed.

5) Although much research has been devoted to the design of thermal management systems, the efficiency and uniformity of various preheating and cooling systems still need to be evaluated in depth.

6) The relationship between the decay rate of the battery cell and the Pack is not yet clear. Because fast charging will magnify the inconsistency. Although many charging and preheating strategies are effective on the battery cell, the effect, feasibility and cost of their application on the pack are still lacking.

Summary

Electric vehicles have higher and higher requirements for fast charging, and existing strategies can no longer meet the demand.

In the future, power station replacement will be the most sought-after market.

It is believed that through the research and development of more fast charge car battery products and the improvement of charging and battery swapping, the range anxiety of electric vehicles in the future will gradually be resolved.