Rechargeable Lithium ion battery life

If you charge it every 3-4 month , it should be fine for a couple of year (lifespan). Lithium battey keep their charge very if you compare them to nimh and low self discharge NIMH.

To get the maximum lifespan out of any lithium-ion battery, you just need to follow a few simple rules:

1. Never let them run dead.
2. They don't like to be to fully charged so charging a lithium battery every few months is a BAD idea. Only charge them when they are running low and ideally rarely charge them until they are full. If you can, charge them up to 80%.
3. Short charges are better than long charges - it's better to charge them multiple times for a short time than one long charge.
4. Without charging them fully, lithium battery meters (those that tell you how much charge is left) will start to become uncalibrated - ie less accurate. You need to charge the battery fully ONCE in a while to recalibrate.
5. Any lithium ion battery that is going to be stored for a time should be stored at about 40% charge.

A lithium ion battery that's allowed to fully discharge will appear to be dead and will not accept a normal charge. It needs to be kick-started with a higher voltage to get it going again. This needs to be done carefully as the batteries can explode or catch fire if excessive voltage applied.

Jimbobs wrote: ↑ A lithium ion battery that's allowed to fully discharge will appear to be dead and will not accept a normal charge. It needs to be kick-started with a higher voltage to get it going again. This needs to be done carefully as the batteries can explode or catch fire if excessive voltage applied.

Depends on the battery... individual cells -> yes as you can apply that charge to the cells themselves. battery packs - > maybe at best as the battery management system may not allow a charge to be accepted and since it's a sealed pack, you won't have access to the cells themselves.

craftsman wrote: ↑ Depends on the battery... individual cells -> yes as you can apply that charge to the cells themselves. battery packs - > maybe at best as the battery management system may not allow a charge to be accepted and since it's a sealed pack, you won't have access to the cells themselves.

Can't speak for all batteries but it has worked for me on both individual cells and battery packs. Obviously the voltage applies is much higher in the case of the battery packs. Maybe I've just been lucky

Thanks for the tips all. But let's say if I didn't follow those suggestions and just left it as is unused for a couple of years. Would it still have the same charging capacity? I understand it would lose its charge over time but my question is regarding the charging capacity.

Jimbobs wrote: ↑ Can't speak for all batteries but it has worked for me on both individual cells and battery packs. Obviously the voltage applies is much higher in the case of the battery packs. Maybe I've just been lucky

It's a design thing... if the battery management system is built into the pack AND it is designed to be powered from the pack, then when there is not enough power being supplied by the pack, then battery management system won't power up and won't function. If you go on e-Bay or Aliexpress and look at DIY power banks where the user supplies the cells, you will find a few who will only function if charged cells are installed initially (ie the battery management unit is powered on by the batteries)... if the cells aren't charged, the pack won't charge.

narmak wrote: ↑ Thanks for the tips all. But let's say if I didn't follow those suggestions and just left it as is unused for a couple of years. Would it still have the same charging capacity? I understand it would lose its charge over time but my question is regarding the charging capacity.

Depends on the design. If the pack has a battery management unit solely powered by the pack's cells, then once the pack goes dead, the pack won't charge whcih means a 100% in capacity. As for charging a cell by itself back to full capacity from dead, the current internet thoughts on that is it won't.