faulty batteries or faulty flashlight or user error?

[enforcer]

Haven't been on here for a while as been well busy and also forgot about this site. :o

I got the Nitecore D20 back in very beginning of dec 2009 so it's still under warranty.
However the flashlight was running great on max-high for just over an hour, (using 1 set, then the other) in the 4 pack of AA sanyo enloop batteries, after all 4 went down to 50% light output on max.
I don't have a sanyo enloop charger, but for some weird reason on the batteries it says only use a sanyo charger.
So thought it would be fine using my uniross nimh charger which has built in protection that shuts off the charger when fully charged,etc.

They looked like they charged up fine, but now they only last like 10-15 mins on max setting on the Nitecore D20, before they rapidly drop to 50%. :mecry::thumbsdow

I can't see why sanyo enloop batteries need a sanyo charger? So either I got faulty batteries, the charger doesn't charge that type properly.
Or my flashlight has suddenly gone wrong.

Or could have damaged the batteries I guess.

Any help, would be great...

 

[Mark620]

They looked like they charged up fine, but now they only last like 10-15 mins on max setting on the Nitecore D20, before they rapidly drop to 50%. :mecry::thumbsdow

I can't see why sanyo enloop batteries need a sanyo charger? So either I got faulty batteries, the charger doesn't charge that type properly.
Or my flashlight has suddenly gone wrong.

Or could have damaged the batteries I guess.

Any help, would be great...

You could have over discharged the batteries...:poof:

 

[Niconical]

Haven't been on here for a while as been well busy and also forgot about this site. :o

I got the Nitecore D20 back in very beginning of dec 2009 so it's still under warranty.
However the flashlight was running great on max-high for just over an hour, (using 1 set, then the other) in the 4 pack of AA sanyo enloop batteries, after all 4 went down to 50% light output on max.
I don't have a sanyo enloop charger, but for some weird reason on the batteries it says only use a sanyo charger.
So thought it would be fine using my uniross nimh charger which has built in protection that shuts off the charger when fully charged,etc.

They looked like they charged up fine, but now they only last like 10-15 mins on max setting on the Nitecore D20, before they rapidly drop to 50%. :mecry::thumbsdow

I can't see why sanyo enloop batteries need a sanyo charger? So either I got faulty batteries, the charger doesn't charge that type properly.
Or my flashlight has suddenly gone wrong.

Or could have damaged the batteries I guess.

Any help, would be great...

The "only use a Sanyo charger" thing is just what they put on the pack, all manufacturers do it. You can use any nimh charger to charge any nimh battery. However, how well any charger charges any battery will depend on its quality, and at first glance it seems that the culprit is likely the charger. Can you tell us a little more about it?

On the other hand though, even the harshest of chargers is unlikely to have damaged a set of batts in the short time you've been using the D20, so it could just be a simple case of it not charging the eneloops fully, nothing more than that.

Do you have another charger available? Even a dumb charger, something with a slow charge rate that you can leave on overnight to really squeeze in the juice, that way you can the try a full run on turbo and at least confirm if the batts are good.

 

[enforcer]

The "only use a Sanyo charger" thing is just what they put on the pack, all manufacturers do it. You can use any nimh charger to charge any nimh battery. However, how well any charger charges any battery will depend on its quality, and at first glance it seems that the culprit is likely the charger. Can you tell us a little more about it?

On the other hand though, even the harshest of chargers is unlikely to have damaged a set of batts in the short time you've been using the D20, so it could just be a simple case of it not charging the eneloops fully, nothing more than that.

Do you have another charger available? Even a dumb charger, something with a slow charge rate that you can leave on overnight to really squeeze in the juice, that way you can the try a full run on turbo and at least confirm if the batts are good.

Nope, only the one charger, unfortunately.

Charger is uniross x-press 1000.

Thanks for the help, so far.

 

[Niconical]

I found the user manual for that charger. It chargers in pairs, not individually. This means that it continues charging both until both show as full, so if one of them was not as depleted as the other, that one will be overcharged. Repeat this a few times and it could affect the batteries. The charge rate isn't that high and you haven't had them that long anyway, but charging in pairs (or worse, sets of 4) is never good for batts in the long run, unless it's a particularly slow charge rate to avoid one getting overcharged while the other catches up.

So, options. Start again with a decent charger. It doesn't have to be expensive, jut something that charges each slot individually.
7dayshop have an individual channel charger and cheap eneloops.

Alternatively, if you're interested to know the real answer, you can send them to me and I'll run them through a Maha C9000 and see what's going on with the capacities. I will of course then send them back :)

 

[enforcer]

I found the user manual for that charger. It chargers in pairs, not individually. This means that it continues charging both until both show as full, so if one of them was not as depleted as the other, that one will be overcharged. Repeat this a few times and it could affect the batteries. The charge rate isn't that high and you haven't had them that long anyway, but charging in pairs (or worse, sets of 4) is never good for batts in the long run, unless it's a particularly slow charge rate to avoid one getting overcharged while the other catches up.

So, options. Start again with a decent charger. It doesn't have to be expensive, jut something that charges each slot individually.
7dayshop have an individual channel charger and cheap eneloops.

Alternatively, if you're interested to know the real answer, you can send them to me and I'll run them through a Maha C9000 and see what's going on with the capacities. I will of course then send them back :)

The nitecore D20 takes 2x AA batteries though and when the first pair ran down I never mixed them up with the 2nd pair.

Or are you trying to say that the charger charges both pairs at the same rate?

So if one pair was slightly less charged, and both pairs got charged to their max.
One of the pairs could have got over charged when I charged all 4 of them?

Very nice looking charger(decent features) and great price too on that link you provided, think I'll get that one and some new enloops just to be safe.
Wouldn't want to damage the flashlight...

 

[Niconical]

It's not about the 2 pairs you have, or mixing them, it's about how the charger charges. That model charges in pairs, so the same applies if you charge 2 or 4. So, let's assume you take a pair of eneloops, run them down in the D20, then put them on to charge. One of them is more discharged than the other, but the charger applies the same charge rate to both until both are full. This is fine for the battery that was a little less empty, but the other one is getting a full charge rate forced into it when it is already full, waiting for the other to chatch up. Repeat this a few times and the batteries are on a slippery slope.

Keeping them in pairs as you have been doing is very good, but charging in pairs doesn't work out well for the batts in the long term.

 

[Surnia]

try a set of alkalines? if you have some fresh ones you can try them out to see if its the flashlight (compare them to selfbuilt's tests to see if they match), and then you can see if its the eneloops or the D20 are at fault.

I'm going to lean to the Eneloops being at fault, but that's due to me grabbing a C9000, and completely ignoring the pair chargers so that I don't have to worry about such a problem.