Cycling 3000mAh nimh - charge/discharge to reform?
03-26-2009, 09:52 AM
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Cycling 3000mAh nimh - charge/discharge to reform?
I picked up the Intellipeak Ice charger mainly for my Rx and Tx packs but I do have a 3000mAh nimh car pack which I want to attempt to reform as it's capacity has decreased as it's sat in my garage for a bit. THe presets in my charger are 1C for charge and 1C for discharge with a 20 minute break between cycles. Is this a good charge/discharge profile to cycle this pack?
Appreciate any input.
somegeek
Appreciate any input.
somegeek
03-26-2009, 10:02 AM
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RE: Cycling 3000mAh nimh - charge/discharge to reform?
Hello
I think 1C is not the most appropriate to reform your pack, common practice is to charge/discharge at 1/10 C so for your pack it is a current of 300mA.
Personally, I hate waiting that long for it to recycle, and I often apply 1/2 C current to reform my batteries after a long storage period.
I do 3 or 4 cycles, maybe a bit exagerated but I feel better that way
I think 1C is not the most appropriate to reform your pack, common practice is to charge/discharge at 1/10 C so for your pack it is a current of 300mA.
Personally, I hate waiting that long for it to recycle, and I often apply 1/2 C current to reform my batteries after a long storage period.
I do 3 or 4 cycles, maybe a bit exagerated but I feel better that way
03-26-2009, 01:40 PM
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RE: Cycling 3000mAh nimh - charge/discharge to reform?
You cannot use a peak detecting charger to form charge. You need a constant current input as close to 0.1C as you can get and then put in at least 150% of capacity (like 15 to 16 hours at 0.1C). If then discharging to determine capacity, you would discharge at 0.3C down to 0.9 volt/cell. If you discharge at a higher rate or fail to discharge down to 0.9 volts/cell, you will get a lower mah reading.
03-26-2009, 02:22 PM
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RE: Cycling 3000mAh nimh - charge/discharge to reform?
ORIGINAL: Rodney
You cannot use a peak detecting charger to form charge. You need a constant current input as close to 0.1C as you can get and then put in at least 150% of capacity (like 15 to 16 hours at 0.1C). If then discharging to determine capacity, you would discharge at 0.3C down to 0.9 volt/cell. If you discharge at a higher rate or fail to discharge down to 0.9 volts/cell, you will get a lower mah reading.
You cannot use a peak detecting charger to form charge. You need a constant current input as close to 0.1C as you can get and then put in at least 150% of capacity (like 15 to 16 hours at 0.1C). If then discharging to determine capacity, you would discharge at 0.3C down to 0.9 volt/cell. If you discharge at a higher rate or fail to discharge down to 0.9 volts/cell, you will get a lower mah reading.
somegeek
03-27-2009, 02:31 PM
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RE: Cycling 3000mAh nimh - charge/discharge to reform?
After a few light cycles try at 80% C an look at the graft cycle if nice an smooth then good batt but when the pack is badly out of it hthen the graph will be all jummppppy an false peaks a lot... LOVE THE GRAFT
Rich
Rich
