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03-09-2009, 07:39 PM   #31
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QuoteOriginally posted by UnknownVT Quote
The optimal charge rate for any NiMH (including eneloops) - is 0.5 - 1C.

Since AA eneloop capacity is 2000mAh (1900mAh minimum) -
that is between 1- 1.9Amps (1,000-1,900mA)
so batteries are charged in about 1 to 2 hours.

Reason: end of charge -dV is more easily detected with 0.5-1C charge rates, below about 0.3C it is almost impossible to detect the -dV end of charge.
The higher the charge rate, the harder it is on the battery chemistry. I charge my Eneloops at 200ma (about 0.1C) and my La Crosse BC-900 charger has never had a problem detecting the battery full condition.

03-09-2009, 08:28 PM   #32
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QuoteOriginally posted by Sean Nelson Quote
The higher the charge rate, the harder it is on the battery chemistry. I charge my Eneloops at 200ma (about 0.1C) and my La Crosse BC-900 charger has never had a problem detecting the battery full condition.
Sorry, it's a myth that lower charge rates are somehow "kinder" on batteries.

There have been many discussion of this over at CPF Batteries section. (please see this post and A look at slow charging )

Battery University on Charging nickel-based batteries from the quote above:

" Nickel-metal-hydride should be rapid charged rather than slow charged. Because of poor overcharge absorption "

0.1C is fine for the initial forming charge - this is normally timed termination at about 12-16 hours - but it is not recommended for regular charging - most cheap dumb chargers are about 0.1C timed (if one's lucky) at 12-16 hours -
one of the most prevalent problems is a tendency for people to charge partially discharged batteries -
then a timed charger will over-charge those batteries......

Last edited by UnknownVT; 03-09-2009 at 09:03 PM.
03-09-2009, 10:19 PM   #33
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All this stuff about charging rate and so on is way over my head. My Maha charger has a conditioning mode so I'm taking it on faith that it will work for me.

As for my Li-Ions, here's what Thomas says about them: "The Moby Power rechargeable lithium battery also has a Rechargeable Battery Safety Unit built in for reliability and safety. This Safety Feature prevents damage to your equipment due to over voltage, unlike other rechargeable CR-V3 rechargeable lithium batteries on the market. This battery is designed to operate within the safe voltage range of an actual CR-V3 lithium battery."

I hope that's safe.
03-10-2009, 08:55 AM   #34
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QuoteOriginally posted by Fnarf Quote
My Maha charger has a conditioning mode so I'm taking it on faith that it will work for me.
It most probably is fine-
the conditioning mode is supposed to be only for occassional use after about 10+ full discharge/recharge cycles.
Let us know the model #

QuoteOriginally posted by Fnarf Quote
As for my Li-Ions, here's what Thomas says about them: "The Moby Power rechargeable lithium battery also has a Rechargeable Battery Safety Unit built in for reliability and safety. This Safety Feature prevents damage to your equipment due to over voltage, unlike other rechargeable CR-V3 rechargeable lithium batteries on the market. This battery is designed to operate within the safe voltage range of an actual CR-V3 lithium battery."
I hope that's safe.
The advert sounds fine.
I think some people may have used these in the K100D -
so may be able to give you direct experience.

03-10-2009, 10:14 AM   #35
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The model number is MH-C800S, as recommended earlier in this thread.
03-10-2009, 11:02 AM   #36
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QuoteOriginally posted by Fnarf Quote
The model number is MH-C800S, as recommended earlier in this thread.
The MH-800S is a very nice charger with 8 independent charging channels.

It has Fast/Rapid and "Soft" charge cycles.

For AA batteries
Fast/Rapid is rated at 1Amp
"Soft" at 0.5Amp.

The Rapid/Fast charge current is preferable as it is exactly 0.5C of the eneloop AA's.

I know this may make people's eyes glaze over -
but from the Duracell Technical document on NiMH batteries -

(and from the various references already given earlier) -
or just trust me on this -
0.5C charge current (=1Amp) is about the ideal for eneloops.

Just a note of interest - the "Soft" charge current of 0.5Amps is 500/2000C of the eneloops = 1/4C - which Duracell Tech Bulletin (Download PDF) says is not recommended for NiMH batteries.......
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