The Most important is the Quality of Cells.

The battery cell quality is most important. What we want to improve is the performance and technology of the battery cells, mainly in the cell consistency. Even if balance is used on the protection board, it has disadvantages and advantages, both in theory and in practical application.

However, in theory, balance has a certain effect, the effect is not much. Why?

Because charging is generally at a current of 2~10 A, and we can only achieve a maximum of 200 mA for equilibrium. This current is too less, and some equalization schemes are started at the end of the charging voltage, which is even more useless.

custom li-ion pack

Energy transfer balance, which allows large-capacity batteries to be transferred to small-capacity batteries by means of energy storage. It sounds very smart and practical. It also divides capacity time balance and capacity fixed-point balance.

It is balanced by detecting the capacity of the battery, but it does not seem to take the battery voltage into consideration. Think about it,

take a 10AH battery pack as an example. If there is a battery pack with a capacity of 10.1AH and a smaller capacity at 9.8AH, the charging current is 2A, and the energy balance current is 0.5A. At this time, the 10.1AH battery needs to be charged with a small capacity of 9.8AH, and the 9.8AH battery charging current is 2A+0.5A=2.5A, then the 9.8AH battery charging current is 2.5A, and then the 9.8AH capacity It is made up, but what is the voltage of the 9.8AH battery?

 

Obviously, it will rise faster than other batteries. If it reaches the end of charging, the 9.8AH battery will definitely be overcharged greatly in advance, in every charge and discharge cycle. The small-capacity battery has been in a deep charge and deep discharge state. There are too many uncertain factors whether other batteries are fully charged. The weak and intuitive ones can only be analyzed here. If there is too much analysis, I am afraid of being incomprehensible.

It is not 100% safe to achieve balanced use of protection boards. Because the protection board is for protection, it only serves as an effective protection for the battery at the most extreme time. It has no ability to improve the performance of the battery. The protection board is only a passive part. Can the protection wire or protection switch at home be improved? Electricity at home? Of course, impossible. It only plays a protective role.