Is running NiMh to empty bad for the battery?

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ezarc
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Is running NiMh to empty bad for the battery?

Im not sure if its it has anything to do with it but I ran 4 eneloops until they were totaly depleted. The LED was basicly moonlight mode and I could stare directly into it and just see a faint glow.

Usually I wouldn’t run them til they are empty but I was doing a “runtime” test and fell asleep so when i woke up it was off but I turned it on again it just had the faint glow like I mentioned before.

I cycled them a few times and they are all close to 100mAh less than what they were last time I measured them and they have had nearly no use apart from that.

And if it is bad for them to run them to dead empty, then I guess remotes and clocks and Wii remotes and other things that use a very small amout of power that will run them til there is nothing left are also bad to use them in?

Anyway just wondering if I did any damage to the batteies or if maybe they just need to be put through the break in mode again. So is it something I should avoid or is it ok to run them empty regurally?

sb56637
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I asked a similar question a long time ago:
http://budgetlightforum.com/node/183#comment-2643

Sounds like it’s not good for a NiMH cell to run it down to 0, although unlike Li-Ion, at least it’s not dangerous to do so.

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ezarc
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Thanks sb56637, just the info I was looking for.

On another note, I asked in another thread over a week ago and didnt get any reply… According to this review of the Ti, a 1.5v alkaline will give 60 lumens for 1 hour and a 1.2v eneloop will give 31 lumens for 2 hours. Is this something to do with the driver in the Ti or is that typical of 1.2v batteries in other lights?

I wish I had 2 identical lights to compare side by side.

neverfeltbetter
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I like this website when it comes to proper usage of NiMH cells:
It’s a german website but the translation seems fine.

click

sb56637
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I’ve noticed that in most of my lights, an Alkaline produces slightly brighter output at first, but it starts to slope off. A NiMH produces slightly dimmer output (but not really significant) for a much flatter output curve. But the Alkaline will produce at least some light for a longer period of time than the NiMH.

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NightCrawl
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I think my mom did the ultimate hardcore test on two Sanyo NiMH cells. They were missing for like two years and were found in a lighting device.. both read 0.5V! I cycled them two weeks on the lowest setting of my BC700 and they regained a capacity of ~2200mAh (claimed capacity is 2600, I have two others that were treated nicely and gave me ~2500mAh)..

I guess you just cant ruin those cells.

garrybunk
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NightCrawl wrote:

I think my mom did the ultimate hardcore test on two Sanyo NiMH cells. They were missing for like two years and were found in a lighting device..

Hmm. . . so you don't want to admit your mom is a flashaholic and you were born into it?  Hmm. . . I have a couch over here that I'd like you to lay down on and tell me all about it.  Smile

-Garry

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