The difference between power battery and capacity battery

When it comes to lithium batteries, I believe there are still many people who don't know much about them, and there are many types of them; today we will share a little knowledge about power batteries and capacity batteries.

The difference between power battery and capacity battery

1. The capacity battery is discharged with a maximum current of 3C

2. Power batteries generally refer to discharge at 5C current, and ultra-high-rate power batteries are discharged at 20C or greater current.

Capacity battery

Mainly to provide products with longer battery life, lithium batteries with energy density as the main research and development direction. With the improvement of technology, the capacity and battery life are gradually improved, and the volume is also becoming smaller.

Application areas: consumer electronic equipment, mobile phone batteries, power banks, etc.

Power Battery

Mainly to provide products with high discharge rate and continuous and stable voltage and current, taking battery safety as the basic principle, and improving the reliability of products during operation as the main research and development direction of lithium batteries.

Simply put, a power battery is a power source that provides a power source for tools. Power batteries require more advanced process control, consistency control and quality management.

Application areas: vehicle power, avionics, drone battery, starting power supply, igniter, etc.

For example, keheng's drone battery, Greg's GensAce vehicle electric avionics, etc. With the improvement of technology, the stability and safety of power batteries are improving year by year.

The difference between power battery and capacity battery

Many people are concerned about the difference between power batteries and consumer-grade batteries. From the battery point of view, there is no essential difference. However, due to the different application conditions of the products, the design concepts and ideas are also different, which leads to great differences in the product attributes of batteries in different fields that we have seen.

1. Different discharge

l  The internal resistance of the capacity battery is large, and the discharge current per unit time is small. Because of the large power of the equipment to be driven, the internal resistance of the power battery is small, and the discharge current per unit time is relatively large.

l  2The power battery adopts double-stacked bipolar lugs in a single unit, or in parallel with a multi-body unit to increase the current of the entire battery pack. The battery capacity is affected by the current at the output end, so the direct effect of parallel connection is The capacity of the power lithium battery pack is increased. The capacity of the battery pack connected in this way is often relatively large, and the discharge current is small due to the large internal resistance, so the continuous discharge time is long.

2. Different voltages

The power lithium battery pack can meet some high-power equipment; the output voltage corresponding to the high voltage will also increase;

The capacity-type lithium battery pack directly increases the current of the entire battery pack in parallel, and the capacity is affected by the current at the output end, so the direct action of parallel connection increases the capacity of the lithium battery pack;

3. Different volumes

l  Capacity batteries are mostly used in consumer products, generally small in size, such as mobile phones, power banks, etc.

l  Power batteries provide power, generally larger in size, such as drone batteries.

4. Different products applied

The voltage value required on some large-scale equipment is high, and the low-power battery pack cannot be operated, so the power-type lithium battery pack must be selected. For example, for the electric bicycles we usually use, the voltage value it requires is often 48V. Compared with some situations in our life, 48V is not small. Therefore, it is necessary to use a power lithium battery pack to ensure the operation of the electric bicycle.

We usually go to some large supermarkets or shopping malls, some sign lights and backup power supplies. Because the power consumption of these devices is not very large, we generally use capacity lithium battery packs, which are different in product application. of.

5. Different internal resistance

The internal resistance of power-type lithium batteries is smaller than that of capacity-type lithium batteries. Taking 18650 as an example, the 3-rate discharge generally has PDC, and the internal resistance is about 40; the 5-rate discharge generally does not have PDC, and the internal resistance is about 20.

6. Cycle life

Capacity batteries are generally consumer electronic products. Because the update iteration is too fast, and the discharge environment is relatively mild, the cycle life is not emphasized in the design.

The use environment of power batteries is relatively bad, and the use cycle of the product is very long, so the cycle life is considered in the design. Although the cycle life of power batteries is very short in actual use, most of them are 300-500 times, but the mobile phone is once a day. It has been used thousands of times for several years in the case of flushing. Some people say that the cycle life of the capacity battery is not as good as that of the power battery. This is not correct; under the same environment, the cycle life of the power battery is much longer than that of the capacity battery. The capacity battery replaces the power battery, and other conditions remain unchanged, it may only be used dozens of times.

There are also safety issues to be aware of

1. Your own safety

Capacity batteries are generally used alone, and power batteries are generally used in groups, which makes the safety design of power batteries more complicated. In terms of heat dissipation, the capacity battery can completely dissipate heat by itself, and the heat dissipation channel should also be considered when designing heat dissipation for a group of power batteries.

2. Product Safety

The capacity battery does not have high requirements for product protection, and most of them are the safety design of the product itself. Therefore, the capacity battery itself only relies on the material and design of the battery on the basis of higher energy density to withstand various safety-threatening situations.

The product body of the power battery is generally of higher value and has more design redundancy. Better diaphragms, foils and casings, more external protection circuits, and heat dissipation layouts are used to ensure the safety of the product body. Of course, it can also be used under harsher conditions (higher external voltage, higher current, more complex external environment).

Therefore, different lithium batteries are required in different environments, and the one that ultimately meets your own needs is the best!