I have a set of two GP300's that originally came with Motorola HNN9620B Ni-Cd 1200mAh battery packs, and HTN9702A desk-top chargers with 12VDC, 200ma power packs.
I've recently replaced the Ni-Cd batteries with Ni-Mh 1800ma batteries. Can I still charge the new Ni-Mh batteries in the desk-top chargers?
From what I've read the biggest problem with charging Ni-Mh batteries is under charging (usually cause by timers, or other auto charging devices), or over charging. I also read that Ni-Mh batteries can be charged at a rate of 10% of their mAh capacity, which would be 180ma. The NTN9702A from what I can tell is a dumb charger. So I think at 200ma I should be ok as long as I don't charge them too long. It's referred to as a 10 hour charger, buy my math says it might charge the Ni-Mh batteries in about 6.75 hours.
I arrived at this conclusion based on the following. Motorola makes a fast charger (90 minute), HTN9042A, for both Ni-Cd, and Ni-Mh batteries. It charges at a rate of 900ma. So the difference between the two chargers is 700ma, or a factor of 4.5. So if I multiply 90 minutes by 4.5 I get 405 minutes, or 6.75 hours.
Does this make sense, or am I missing something?
Thanks,
Bill
I've recently replaced the Ni-Cd batteries with Ni-Mh 1800ma batteries. Can I still charge the new Ni-Mh batteries in the desk-top chargers?
From what I've read the biggest problem with charging Ni-Mh batteries is under charging (usually cause by timers, or other auto charging devices), or over charging. I also read that Ni-Mh batteries can be charged at a rate of 10% of their mAh capacity, which would be 180ma. The NTN9702A from what I can tell is a dumb charger. So I think at 200ma I should be ok as long as I don't charge them too long. It's referred to as a 10 hour charger, buy my math says it might charge the Ni-Mh batteries in about 6.75 hours.
I arrived at this conclusion based on the following. Motorola makes a fast charger (90 minute), HTN9042A, for both Ni-Cd, and Ni-Mh batteries. It charges at a rate of 900ma. So the difference between the two chargers is 700ma, or a factor of 4.5. So if I multiply 90 minutes by 4.5 I get 405 minutes, or 6.75 hours.
Does this make sense, or am I missing something?
Thanks,
Bill
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