Battery Testing? NiMH

[Samuel Hagan JR]

Is there a way to test the integrity of a battery pack like you would a car battery. It's a NiMH.

 

[Michael Costanzo]

Is there a way to test the integrity of a battery pack like you would a car battery. It's a NiMH.

hi sam,i have a small Hobbico battery tester that puts a small load on Battery pack.if not i would charge up the pack as much as it will take under normal charge and turn on boat or radio and see how long to get down to 6v. i just bought a bunch of Tenergy (sold thru Maxxpacks on e-bay) battery packs (flat and hump/6v) and they were like $16 Each. "when in dout,throw it out"" not worth wrecking a boat over a few dollars.PS and i always keep a charged spare pack in field box,mike.

 

[Samuel Hagan JR]

I always charge my battery packs the morning of the race. I have spare packs. I don't see an issue with them at the moment but wasn't sure if there was a way on actually testing them. I'll look into the Hobbico tester.

 

[Michael Costanzo]

I always charge my battery packs the morning of the race. I have spare packs. I don't see an issue with them at the moment but wasn't sure if there was a way on actually testing them. I'll look into the Hobbico tester.

the biggest problem is trying to find a tester that can put such a small load on the batteries.

 

[mercguy]

Michael

If you can get to the leads to test the voltage you can put a 40 ohm resistor in series with the positive lead on the voltmeter to the battery and this will put about a 150 mA load on the battery . This is about the load that a system puts on the battery not including the servos. The resistor should be a 2 watt or more rating. They do get warm. You can buy them at Radio Shack. It may sound complicated but it is straight forward.

Bill

 

[David Murany]

We use a Yuntong charger and always discharge/charge our packs. This way you can monitor the milliamps removed and put back. If the milliamps put back in start to become lower than when it was new, toss it.

 

[Michael Costanzo]

hi david and bill,that's some very good info to go by.thanks,mike.

 

[Samuel Hagan JR]

Michael

If you can get to the leads to test the voltage you can put a 40 ohm resistor in series with the positive lead on the voltmeter to the battery and this will put about a 150 mA load on the battery . This is about the load that a system puts on the battery not including the servos. The resistor should be a 2 watt or more rating. They do get warm. You can buy them at Radio Shack. It may sound complicated but it is straight forward.

Bill

When you do this are you measuring the Voltage Drop?

 

[mercguy]

Michael

I was wrong the way I described it. The resistor should go across the plus and minus leads which would put a load on the battery pack. With the resistor in place you can then check the voltage across

the leads and see how much it goes down. This is what a battery checker does. It puts a load across the battery and lets you see the voltage drop. Sorry about the misinformation.

Bill

 

[Michael Costanzo]

Michael

I was wrong the way I described it. The resistor should go across the plus and minus leads which would put a load on the battery pack. With the resistor in place you can then check the voltage across

the leads and see how much it goes down. This is what a battery checker does. It puts a load across the battery and lets you see the voltage drop. Sorry about the misinformation.

Bill

hi bill,i thought is was not right the fist time you posted, but i knew which way it needed to be.thanks again,mike.

 

[Samuel Hagan JR]

Michael

I was wrong the way I described it. The resistor should go across the plus and minus leads which would put a load on the battery pack. With the resistor in place you can then check the voltage across

the leads and see how much it goes down. This is what a battery checker does. It puts a load across the battery and lets you see the voltage drop. Sorry about the misinformation.

Bill

Geez. Thanks for answering my question.

 

[Michael Costanzo]

Michael

If you can get to the leads to test the voltage you can put a 40 ohm resistor in series with the positive lead on the voltmeter to the battery and this will put about a 150 mA load on the battery . This is about the load that a system puts on the battery not including the servos. The resistor should be a 2 watt or more rating. They do get warm. You can buy them at Radio Shack. It may sound complicated but it is straight forward.

Bill

When you do this are you measuring the Voltage Drop?

sam,yes you are measuring the Voltage drop.forgot exactly what voltage you are not supposed to go below for each cell,but there is a certain volt for each type of cell..lipo,nimh,etc.