Sanyo Eneloop 3UTGA usage question

[jay48]

Hello,
After reading about Sanyo Eneloops at this forum, I bought 4 of the new '1500' Eneloops last December to be used with my camera (Sony DSC W1). The charger I have is a Sony BC CS2B that was included with the camera. I have read the article here about that charger as well and learnt that it was OK for the Eneloops. When the first two batteries had been used up and required to be recharged, I calculated the time needed as 5 hours (2000mAh divided by 400mAh output of the charger). Therefore I removed the batteries from the charger after 5 hours (before the indicator light went out). Then I started using the other set of batteries. After they got depleted (about two months after) I put the first set into my camera but they show a low level of charge! What's strange is that after I charged them (and before storing them) they showed a "full" bar. The batteries were slightly warm (not burning hot) when they were being charged. I don't want to ruin these batteries because I've ruined two pairs of rechargeable NiMH batteries that were used with my camera! (I think the camera's jinxed:devil:).
The output of this charger is 400mAh, I've read that the ideal rate for Eneloops is 100mAh-200mAh. So should I change my charger?
Any reply is appreciated!
Regards.

 

[Aquanaut]

When the first two batteries had been used up ...

After they got depleted ...

:welcome:

I can only guess that you are discharging the batteries to a very low voltage. Did you measure the voltage "after depletion"?

NiMH batteries last longest when they are recharged well before they are fully depleted.

400 mA is a good charge rate, but it is best if they do not get warm during charge. Get yourself the MH-C9000 for best battery life.

Here are the specs on the charger.

 

[SilverFox]

Hello Jay48,

Welcome to CPF.

The charge acceptance is not 100%. It looks like your charger charges at 400 mA, but it will take longer than 5 hours to achieve a full charge.

You ended up putting partially discharged cells into your camera and this resulted in the poor performance.

It is better to leave the cells in the charger until it signals that the charge has been completed.

On a flashlight forum where people are as fanatical about chargers and batteries as they are about flashlights, the advice is always that you NEED a new charger... :)

It is better to charge cells individually rather than in pairs, so look for a charger that can charge at 1000 mA and charges cells individually. A popular charger around here that works very well is the Maha C9000. It is not perfect, and there are other chargers you can choose from, but it is set up to help you get more life from your cells.

Tom

 

[SilverFox]

Hello Aquanaut,

I believe those specifications are trying to say that the charger charges AA cells at 400 mA and AAA cells at 160 mA.

Tom

 

[mfm]

The output of this charger is 400mAh, I've read that the ideal rate for Eneloops is 100mAh-200mAh. So should I change my charger?
Any reply is appreciated!
Regards.

The ideal rate is 1000mA - 2000mA. The Sony is not that great for Eneloops...

 

[jay48]

Hello!
Thank you for your welcome & replies. I'm sorry for the delay in replying (what with the ICC Cricket world cup quarter finals and all:laughing:). I will charge this pair again and this time keep it till the signal-lamp goes off and post the results. Regarding checking the voltage; I don't know how to check the voltage but I have a digital multimeter. I can give it a try if you tell me how!
I usually remove the batteries from my camera the moment it says "battery low", is this depleting it too low?
I'll check the price of the C9000 and locate one. I'm in Sri Lanka so postage is usually a deal-breaker:sigh:
Regards.

 

[Russel]

[...] Regarding checking the voltage; I don't know how to check the voltage but I have a digital multimeter. I can give it a try if you tell me how!
[...]

Here is a good message thread that is very informative about using your multimeter. If you scroll down a bit there is a section on measuring battery voltage. I do suggest that you read the entire post - lots of good information!.
Simple guide to using a DMM for measurements

 

[jay48]

Here is a good message thread that is very informative about using your multimeter. If you scroll down a bit there is a section on measuring battery voltage. I do suggest that you read the entire post - lots of good information!.
Simple guide to using a DMM for measurements

Thank you, Russel, I will read that and give it a shot. The second pair signalled 'low battery' yesterday so I've got to charge these as well.

 

[jay48]

I checked the voltage of the batteries (that were depleted) and one read 1.24V while the other read 1.14V. [I selected '20V' on the multimeter to get these values]
The current pair I am using on my camera read 1.24V each (the camera meter signals 'half-battery'). So, is one battery messed up? I will be charging the first pair tomorrow. BTW this article on multimeter usage is brilliant! I bookmarked it for future use.
Regards.

 

[Mr Happy]

I checked the voltage of the batteries (that were depleted) and one read 1.24V while the other read 1.14V. [I selected '20V' on the multimeter to get these values]
The current pair I am using on my camera read 1.24V each (the camera meter signals 'half-battery'). So, is one battery messed up? I will be charging the first pair tomorrow. BTW this article on multimeter usage is brilliant! I bookmarked it for future use.
Regards.

First of all, both batteries ought to read more or less the same voltage. If that doesn't happen, they are unbalanced. A reading of 1.14 V on a multimeter indicates a battery that is completely discharged, possibly over discharged. A better reading for a discharged battery is 1.20 V. A battery reading 1.24 V still has some charge left in it, perhaps 25% or so. A fully charged Eneloop should read 1.33 V or more, depending on how long it has been sitting unused.

That means, for example, that if both batteries are at 1.24 V the camera should show them as being half empty at best. So in your case the camera seems to be correct.

You should put two batteries in your charger, charge them up and then see what the multimeter reads after a few hours. If the batteries are good, the voltage should be about 1.38 V or more and the camera should show full.

Incidentally, why don't you put the meter on the 2 V range rather than the 20 V range? It will be more accurate on 2 V.

 

[jay48]

First of all, both batteries ought to read more or less the same voltage. If that doesn't happen, they are unbalanced. A reading of 1.14 V on a multimeter indicates a battery that is completely discharged, possibly over discharged. A better reading for a discharged battery is 1.20 V. A battery reading 1.24 V still has some charge left in it, perhaps 25% or so. A fully charged Eneloop should read 1.33 V or more, depending on how long it has been sitting unused.

That means, for example, that if both batteries are at 1.24 V the camera should show them as being half empty at best. So in your case the camera seems to be correct.

You should put two batteries in your charger, charge them up and then see what the multimeter reads after a few hours. If the batteries are good, the voltage should be about 1.38 V or more and the camera should show full.

Incidentally, why don't you put the meter on the 2 V range rather than the 20 V range? It will be more accurate on 2 V.

So I'll charge the pair with the 1.14V battery and then measure the voltage again using 2V. Then I'll recharge the current pair.
Thanks!

 

[jay48]

I charged the batteries and after about one hour, the charger LED started flashing! I've never come across this signal and the batteries were not charging, so I disconnected it. I think I need a new charger!
Also, both battery sets have one battery that has a lower voltage. I don't think this is normal, isn't it supposed to be equal?

 

[Mr Happy]

I charged the batteries and after about one hour, the charger LED started flashing! I've never come across this signal and the batteries were not charging, so I disconnected it. I think I need a new charger!
Also, both battery sets have one battery that has a lower voltage. I don't think this is normal, isn't it supposed to be equal?

So what are the voltages of the four batteries right now? We can't say anything if you don't tell us what you are seeing.

 

[yliu]

I've read that the ideal rate for Eneloops is 100mAh-200mAh.

I've been charging my eneloops at 2100mA, for quite a while now and I didn't noticed any damage in the batteries.

 

[jay48]

So what are the voltages of the four batteries right now? We can't say anything if you don't tell us what you are seeing.

Sorry about that! The voltages of this pair is 1.32V and 1.34V. The charger blinks after about half hour. Usually the charger light goes off but this is the first time this happened. I haven't used the charger after this incident because I don't want to ruin my Eneloops!

 

[Mr Happy]

Sorry about that! The voltages of this pair is 1.32V and 1.34V. The charger blinks after about half hour. Usually the charger light goes off but this is the first time this happened. I haven't used the charger after this incident because I don't want to ruin my Eneloops!

How long has it been since those batteries were on a charger? Have they been used at all since then? Basically, those voltages indicate they are more or less fully charged. Why don't you use them in something to run them down, and then try charging them after they are partly or fully drained?

 

[jay48]

How long has it been since those batteries were on a charger? Have they been used at all since then? Basically, those voltages indicate they are more or less fully charged. Why don't you use them in something to run them down, and then try charging them after they are partly or fully drained?

They were used in the camera and once it signaled 'half' I charged them. The charger started flashing before 5 hours (I think after about two hours). I must also say that the temperature in Sri Lanka is about 34-35 degrees on average during the day (something to do with the equinox) so maybe the temperature was too high?
I'll use these on the camera, check the voltage and then pop them in the charger.
Thank you!