Battery what to do

[Albinoni]

Got a question here re my Eneloops. Now when I have my torch on say for 2 mins or so the LED slowly fades off which tells me the batt is weak and loosing its power/charge. But if say I dont use the torch doe about 10 mins and turn it back on it is back to normal and bright again but after another 2 mins or so it slwoly fades off.

I know when you buy Eneloops they come charged up so dont need to charge.

So if this is happening to me what do I need to do and what is this telling? Would I now need to recharge my Eneloop or just keep using the same battery till its fully dead.

 

[Marduke]

Got a question here re my Eneloops. Now when I have my torch on say for 2 mins or so the LED slowly fades off which tells me the batt is weak and loosing its power/charge. But if say I dont use the torch doe about 10 mins and turn it back on it is back to normal and bright again but after another 2 mins or so it slwoly fades off.

I know when you buy Eneloops they come charged up so dont need to charge.

So if this is happening to me what do I need to do and what is this telling? Would I now need to recharge my Eneloop or just keep using the same battery till its fully dead.

1) You need to charge your Eneloops out of the package to top them off for use.
2) It's possible, depending on the light in question, that the LED is simple dimming because of heat buildup. That would happen if the light in question has poor thermal management.

 

[Power Me Up]

I have to disagree with Marduke here.

Although you can charge Eneloops out of the package to top them off before use, you don't need to do so. They come out of the package with around 70-75% of a full charge. Although I normally do a discharge out of the package on my Maha C9000 before doing a full charge and then put them into use, there are plenty of reports of people taking them straight out of the package and using them in their digital cameras for months and taking hundreds of photos before needing to charge them for the first time.

Although heat build up can cause an LED to fade somewhat, it sounds to me like it's dimming a lot more and a lot quicker than what would be normally expected... What sort of torch are you using? How much use have those Eneloops had since you bought them?

I'd suspect that they are indeed fully discharged and need to be recharged. It's quite normal for the voltage of batteries to recover after a rest, but you can't expect to get much more energy out of them by letting them rest. Depending on the torch, if it uses 2 or more cells it could actually be causing damage to your Eneloops with what you're doing - if one cell was holding more charge than the other, it could end up reverse charging the other which isn't good for any cell.

I'd suggest giving the cells a charge and try them again and see how you go!

 

[Albinoni]

I have to disagree with Marduke here.

Although you can charge Eneloops out of the package to top them off before use, you don't need to do so. They come out of the package with around 70-75% of a full charge. Although I normally do a discharge out of the package on my Maha C9000 before doing a full charge and then put them into use, there are plenty of reports of people taking them straight out of the package and using them in their digital cameras for months and taking hundreds of photos before needing to charge them for the first time.

Although heat build up can cause an LED to fade somewhat, it sounds to me like it's dimming a lot more and a lot quicker than what would be normally expected... What sort of torch are you using? How much use have those Eneloops had since you bought them?

I'd suspect that they are indeed fully discharged and need to be recharged. It's quite normal for the voltage of batteries to recover after a rest, but you can't expect to get much more energy out of them by letting them rest. Depending on the torch, if it uses 2 or more cells it could actually be causing damage to your Eneloops with what you're doing - if one cell was holding more charge than the other, it could end up reverse charging the other which isn't good for any cell.

I'd suggest giving the cells a charge and try them again and see how you go!

The torch I'm using is a MX Power LED which takes 1xAA battery. I also believe that it uses a Luxeon LED but dont quote me on that. Also the LED is a 1watt.

When I bought the Eneloops I did not charge them at all but I do use it everyday at work for my job as a maintenance technician. It's not very heavily used but like I said it's used.

I can't quite understand how a torch can actually cause damage to a battery such as an Eneloop, and I purposely went Eneloops as I've heard on this forum they perform very well for torches and in some ways better than your standard Alkaline. When you say Cell your refering to a battery ?

Also while on this duscusing I'm planning to buy a Maha 9000 as I've heard some good things about them.

Thank you.

 

[Marduke]

Save yourself a lot of head scratching and try charging the cell, and see what your light does then.

 

[Power Me Up]

The torch I'm using is a MX Power LED which takes 1xAA battery. I also believe that it uses a Luxeon LED but dont quote me on that. Also the LED is a 1watt.

When I bought the Eneloops I did not charge them at all but I do use it everyday at work for my job as a maintenance technician. It's not very heavily used but like I said it's used.

Maybe it's flat, try charging it and see what happens. Or alternatively, you've probably got at least one other Eneloop that came with the one that you bought to use in the torch. If you've got unused Eneloops, you could also try them...

I can't quite understand how a torch can actually cause damage to a battery such as an Eneloop, and I purposely went Eneloops as I've heard on this forum they perform very well for torches and in some ways better than your standard Alkaline. When you say Cell your refering to a battery ?

What most people refer to as a battery is actually just a cell. A battery is a collection of cells joined together. The exceptions would be 6V and 9V batteries which are normally comprised of 4 and 6 cells respectively.

Since you've got a single cell torch, you don't need to worry about having your cells reverse charged. It's still not good to leave them in a deeply discharged state for an extended period of time, but the damage from doing so would be relatively minimal...

Also while on this duscusing I'm planning to buy a Maha 9000 as I've heard some good things about them.

Yep, that's certainly a good idea. Since you've got a single cell torch, it's good to have a charger which has independant channels for each cell rather than having to charge them in pairs.

 

[Albinoni]

Ok thanks for your help everyone. Yes perhaps my eneloops were quite low on charge when I bought them, so I will re-charge them back to full capacity and let you all know how I went.

BTW: At the moment now I'm using a new Duracell Procell in it and will see how long that lasts.

But like I said I'm sure my eneloops were probably less than half full when I bought them.

 

[mdocod]

over-discharging a NIMH will damage it. When things start to dim a lot it means the cell is falling on it's face, letting the light continue to run in a very low output is hard on it.