a few different charging questions (nimh and lion)

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dead led
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a few different charging questions (nimh and lion)

hi, i have a few different charging questions that ive been wondering about lately so its about time i asked them Silly

my chargers are tr-001 black model, sanyo nimh, and a accucell 6.

1- i have a baby rocker that runs on 4 x d’s but i run it on eneloops with 2aa to d converters (wish there were 3aa to d), so is it ok to charge them in the converters in series? that’s 4s2p yeah? i use the old quick clamp with screws as seen on here before.

2- generally if im charging multiple nimh with the accucell should i do series or parallel?

3- my 2yo tf flames 2400 come off the tr001 at about 4.17 or 4.18 but with the accucell 6 they only get to 4.14 or 4.15 why is that? just tried charging a (full) cell again at .5a and voltage only increased .01 after a hour on charge??

4- I also notice that the accucell voltage reads higher on charge and lower on discharge than my (cheap) dmm, the difference is obviously between the batt/charge leads and what the charger is telling me. whats up with that?

5- when i got my accucell i tested the capacity of a 3yo near dead makita drill battery, straight off the charger it would only screw in a few screws then struggle, anyway it still measured about 900mah of 1.3ah which seems better than real world use. the thing is it would only discharge at .3a?? this is high resistance right? anyway to revive the battery? i have tried deep discharge followed by high amp charge a few times, did nothing.

had more but i forget so that will do for now.

thanks.

dead led
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Oh and in an noobie attempt to get the cell up to read 4.2 I put it on nimh for a couple of seconds at .5a and it read 4.18 on charge, then tried .7 and it tripped the protection but it won’t reset, tried in a light, tried in the tr001 and nuthin. Accucell says connection break.

Can I reset it?

ryansoh3
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1 and 2. It’s best to charge Ni-MH’s individually, as they use a special (and sensitive) way to detect their full charging capacities. If that’s not possible, use series charging, but not parallel charging.

3. Your Accucel might be out of calibration. Press and hold the 2nd and 4th buttons from the left (I think) while plugging in the power to calibrate it.
It’s also because the Accucel uses a proper li-ion termination technique (ends at 10% of the initial charge current) compared to trickle charging in the cheap charger.

4. The while the Accucel is a very capable hobby charger, it uses cheap parts, including cheap resistors that are not very precise. They exhibit errors that fluctuate depending on the current passing through them. I got frustrated because of these issues and upgraded my charger to the iCharger 106B+.

5. Probably high internal resistance due to age. Is it li-ion or Ni-NH or Ni-Cd?

6. Yeah, try not to do that. Let the cell rest for a while so that the voltage drops, and then put it in a light. What brand is it?

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dead led
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ryansoh3 wrote:
but not parallel charging…………….. _ i think i have read that before,but why not?? same packet batterys would/should have a very close delta v point and paralell batts equalize too dont they so i dont understand the the technical reason for it being not recomended, do u know more about it? _

5. Probably high internal resistance due to age. Is it li-ion or Ni-NH or Ni-Cd? ………………. nicd

6. Let the cell rest for a while so that the voltage drops, What brand is it? + ……………….tf flame 2400, yes i knew i was experimenting with my battery but i was curious, the cell was 4.09 resting before and can still read 3.85 after it tripped but wont charge or work in light +

ryansoh3
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Unlike li-ion, Ni-MH’s don’t easily balance out, unless you put them in parallel for a long time. (24+ hours)

Some chargers do charge them in parallel in sets of two, but they are not recommended.

More info here: http://www.candlepowerforums.com/vb/showthread.php?159764-A-look-at-NiMh...
and here: http://www.candlepowerforums.com/vb/showthread.php?317522-Charging-10-AA...

Yup, Ni-Cd is pretty much phased out for its toxicity and notorious memory effect.

I suggest your get some good Panasonic cells, TF ones you should really stay away from.

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dead led
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Thanks, I have 2 Sanyo and 2 panasonics in the mail, should be here soon.

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Great, feel free to ask any questions, we’ll try our best to answer them.

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dead led
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Thanks, I intend to.

Btw, that battery still won’t work, guess its toast. Must not reset itself.

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dead led wrote:
Thanks, I intend to.

Btw, that battery still won’t work, guess its toast. Must not reset itself.


I don’t have any tf flames, but all of my protected cells can be reset by briefly connecting it in parallel with another liion cell.