NiMH battery charging

[Paul75Participant @paul75]

Hello Everyone.

Apologies that this is probably going over old ground but do rechargeable NiMH batteries need discharging first after use before they are fully charged again?

The reason I ask is that I have a new charger which has a discharge facility and I've read that some battery types exhibit "memory" if they are charged incorrectly. I also have some new NiMH batteries and would like to keep them working well for as long as possible.

Many thanks,

Paul.

[Paul75Participant @paul75]

[Dave MilbournParticipant @davemilbourn48782]

Paul

The 'memory effect' was attributed to Nickel-Cadmium batteries, which are no longer available – well, not legally! NiMH batteries don't suffer from this at all, so it's OK to part-discharge them and then just top them up. I would, however, recommend a full discharge/recharge cycle every once in a while. Also don't fast-charge them for the first 4-5 charges from new; the charge rate should be built up gradually. On the question of the charging current I never charge batteries at more than their C rate. This is the stated capacity of the pack without the time factor e.g. a 3200mAH pack's C rate is 3200mA. If you charge the pack overnight at something like C/10 then you'll never overcharge the cells.

Dave M

[Paul75Participant @paul75]

Dave

Thanks for your reply – it'll allow me to keep my batteries in fine fettle.

Paul.

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