CAP232CM

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Hi I just bought a 4.8V 2700mAh NiMH pack. I want to know how to charge and discharge it the right way. The chargers I have are a Hobbico multi charger, Super Nova, Integy 16x2 version 2.5, and a Hitec CG 330.

The instructions that came with the battery say to charge the 2700 at a 2000mA rate. What does this mean? Do these packs develope a memory? Can I just charge it at a C/10 which I think would be 270mah? Can I use my Hobbico Multi charger at the 250mah rate and just charge for 14 to 16 hours?

I'm a newbe to NiMH so I need some serious help. I to have done some searching on here but the info is a little overwhelming and hard to figure out. If someone could explain this to me in lamens terms I would appreicate it. Thanks!

thomasb

It means that you can use a delta peak fast charger set to 2000mA. Charge time would be about 1.5 hours on a moderately discharged pack. If you stick with the typical 1C rates, 2700mA can be used to charge it.

NiMH chemistries do not develop memory issues. But frankly, in our R/C hobby application, neither do NiCd's.

Sure. That is a safe thing to do. In fact, the VERY first charge should be C/10 to balance the cell voltage (avoid a fast charge on the first use).

Sure. FWIW, fifteen to seventeen hours would be ideal for a 250mA rate into a 2700mAH pack.

d4a2n0k

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In addition to the original question, I also just got my first NiMH receiver pack also 2700 Mah but in a 6 volt version. For the first charge I used the Hobbico Multi Charger at a 250 mah charge rate for 16 hours and everything went fine.

My question is, without a peak charger, how will I know how long to charge from now on? I have heard horror stories about NiMH packs blowing up and obviously dont want the same to happen to me. Do I charge until the pack gets warm or do I need to get a peak charger for it? For the first charge it was not a problem because the pack was dead but after the first use and say with 60 % capacity left on the pack, how will I know when to stop charging?

Do I need to bite the bullet and spend the money on a peak charger?

thomasb

If you are charging a 2700mAH pack at 250mA (~C/10) it will not blow up, melt, catch fire, or whatever else you may have heard. Those sort of things can happen, but not at that wimpy charge rate.

Do not get nit-picky about leaving it on for a few extra hours. It takes a long time for a constant C/10 rate to impact cell health. But I do suggest you upgrade your charge system to one that measures capacity. You will want to do this on a periodic basis to check pack health.

CAP232CM

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Thanks Thomas!