Is it worth it to train lithium batteries?

Question

Batteries

Hello!
The day before yesterday they gave me a rechargeable flashlight, because. the previous owners had a charger blown right in the outlet (one electrolytic capacitor exploded and turned the floor of the circuit). The flashlight has not been used for several years and the battery, accordingly, has not been charged. As soon as I got the flashlight, I measured the voltage on the bank, it was about half a volt. I immediately charged it with a Chinese module based on TP4056. Yesterday I actively used it all day in different situations (shone where it is possible and impossible). By evening, it began to shine much worse. It seems to me that the battery should not have been discharged so quickly.
Actually, the question: is it worth it to carry out several cycles of full discharge / charge if there is only a Chinese charger module for lithium based on TP4056 among the chargers?

Answer 1

The answer has two parts ;)
The first is that it is useless to train lithium batteries. They do not have a "memory effect", roughly speaking, the plates are not clogged with insoluble salts and there is no need to try to dissolve them, they are set to zero and charged back to the stop.
The second part of the answer is that lithium batteries need to be pumped. By itself, a lithium (and derivative from it) battery is very dangerous. It can catch fire or explode during the most common operation - overheating, hypothermia, overcharging - and hello to fireworks. Samsung S7 will not let you lie. In order to be able to use them, each such battery has its own control circuit built in, which should not allow it to sit lower than necessary, take more charge than necessary, heat up or freeze (the latter is done by an internal short :)). The Chinese, and now 99.99% of the batteries (and not only) are Chinese, they are trying to save money on these schemes. As a result, after a long downtime, this scheme may lose its limits. And then she starts to allow the use of the battery in learning mode - looking for edges:
Therefore, try to plant it once to failure and then charge it at night. May I help.

Answer 2

Training is useless.
About the swing. A new lion battery has an inhibitor that is destroyed after a few cycles. The inhibitor is needed for long-term storage in a warehouse / store. Therefore, the first 2-3 cycles can show very strange capacitance values, after which it levels off.