How many mA does your voltmeter say your NiMH batteries are?

[JEDI]

i have maxell 1400 mAh AA batteries. but the charger light never turns green, no matter how many days i keep it charged.

so i took a volt meter and it said 10 amps?! i measured a regular AA battery (duracell) and it came back as 5 amps.

What does yours say?

 

[neovan]

mine are 1600 maH

i got mine for 4 for $10 which includes the charger...is this a good deal?

 

[NutBucket]

Originally posted by: XFILE
i have maxell 1400 mAh AA batteries. but the charger light never turns green, no matter how many days i keep it charged.

so i took a volt meter and it said 10 amps?! i measured a regular AA battery (duracell) and it came back as 5 amps.

What does yours say?

Are you putting the voltmeter in series with the batteries? (plus to minus plus, plus to minus) Also, measuring in the charger isn't indicative since the charger is flowing current into the cells. Really, if you measure the current flow out of the battery in a given device it isn't indicative either unless the device draws some certain amount. For instance, if your device draws 1600 mA and the batteries power it for about an hour then you could say your cells have a capacity of 1600 mAH. However, devices can draw far more then the rated capacity of a given cell. For instance, R/C car cells now come rated up to 3000 mAH, but the motor/electronices draw about 20A continuous so the cells only last a few minutes.

I hope this makes sense.

 

[JEDI]

the battery is alone. nothing else was attached to it.

 

[Thegonagle]

Your charger might be faulty. If those little batteries are delivering 10A, I believe they are probably charged.

 

[Eli]

Heh... You're not really looking at it right. I don't think you're using the voltmeter right.. because at 10 amps.. the little AA battery would last a few seconds...

If your batteries are 1400 mAh, that just means that they can supply 1400 milliamps for 1 hour.

Or 2800mA for a half an hour.

Or 4200mA for 15 minutes.

Just measure the voltage. If its what the batteries spec, they're fine.

 

[Jerboy]

Originally posted by: XFILE
i have maxell 1400 mAh AA batteries. but the charger light never turns green, no matter how many days i keep it charged.

so i took a volt meter and it said 10 amps?! i measured a regular AA battery (duracell) and it came back as 5 amps.

What does yours say?

Amps ? Do you mean you friggin connected an ammeter across the battery? DO NOT do that, because you're effectively shorting out the battery. You can't measure the capacity of batteries with a simply multimeter. To get any meaningful result, you need a battery analyzer(big bucks)

 

[ElFenix]

like jerboy said, don't do it, its a bad idea.

i remember back when 1700mAh cells were big news for sub-c cells. now they have like 3000s. almost 2x the runtime!

 

[Jerboy]

Originally posted by: ElFenix
like jerboy said, don't do it, its a bad idea.

i remember back when 1700mAh cells were big news for sub-c cells. now they have like 3000s. almost 2x the runtime!

You're really lucky that you only attempted this on a small battery. Ohm's law says I=V/R and ammeter has an internal impedance of 0.05ohm, leads have about 0.05ohm and battery itself has about 0.02ohm. making the system impedance of 0.12ohm, thus limiting to about 10A. Since the current was limited through system impedance, your ass was saved. Say "hmmm I wanna find out what kinda amps I have here" and do something dumb like this on a 96V fork lift battery or low impededance 480/277V main distribution panel, that little multimeter and its leads will burst into a flame.