Quote:
Originally Posted by paulsherwin
You don't actually need output protection if you are prepared to use the cells carefully. This means recharging them well before they are fully drained, which is easy in some applications but more difficult in others. 18650s are pretty cheap, especially if you scavenge them from scrap battery packs, so the cost of occasionally messing things up and wrecking a few cells isn't great.
|
This is true. Due to experience in the day job I may have a tendency to over-engineer battery management systems! One system I designed is rated to discharge its 100Ah battery pack in about 20 minutes and still has to deliver a very long service life (thousands of cycles).
For casual use, there's no problem about just being a bit careful. There is the risk that a seriously over-discharged cell can develop internal short-circuits and thus present a fire or explosion risk when recharged. The mechanism for this is that copper from one electrode starts to migrate through the cell towards the other, aluminium, electrode, which can create a conductive path which is clearly bad news.
Chris