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braxx · 03-30-2009, 08:30 PM

I bought 4 new 1500mAh NIMH battery packs and a new Onyx 240 charger.
I charged all of the packs.
I ran all of the packs down and recharged them again and when they finished charging the charger displayed their capacities as: 1355mAh , 1204mAh , 1200mAh and 1112mAh

Does the Onyx charger display the amount of charge that went in or does it display the total capacity of the battery?

Ie; are these batteries not up to there rating?

SORRY I FORGOT TO SAY THESE ARE 2/3A NIMH.

robbio4422 · 03-30-2009, 08:36 PM

im kinda new to lipo but ima take guess here.... im thinking that you are running your batteries on a lipo cut off... the cut off prevents you from draining the battery completely... the 1200+ that your charger is reading to you could be what the battery is getting back.

from 1500mah. your useing 1200+ and thats what your putting back in.

could be wrong

P1choco · 03-30-2009, 08:49 PM

Might just be what it put in.

Harvo · 03-30-2009, 08:55 PM

I have an Onyx charger. It tells you what it put in. You don't drain your batteries to zero so the number will always be different and usually lower than 1500. Don't run your nimh batteries all the way down!

robsdak · 03-30-2009, 08:56 PM

how many time have you charged them? the first charge should have been 10% of the capacity. it takes several cycles to get a full charge.

i have a couple Team Orion 3000mAh that will charge to 3700mAh. but i was told at the time i bought them, they would hold more. this is just as far as i have pushed them.

braxx · 03-30-2009, 09:14 PM

This was only my 2nd charge on them.
I'm happy if that is the amount of charge put into them.

Duuuuuuuude · 03-30-2009, 09:19 PM

It shows how many mah's it put in, not how much it has total.

robsdak · 03-30-2009, 09:24 PM

get yourself a good meter like a Fluke and test them after they are charged. you will find as you charge them more they will hold what they are supposed too.

Duuuuuuuude · 03-30-2009, 09:37 PM

Quote:

Originally Posted by robsdak

get yourself a good meter like a Fluke and test them after they are charged. you will find as you charge them more they will hold what they are supposed too.

The Onyx will tell you nearly everything you need to know (mah applied, voltage, time charged, etc). The seperate meter would be overkill. My Fluke has never seen a battery since I got my 240...

braxx · 03-30-2009, 09:45 PM

Quote:

Originally Posted by robsdak

get yourself a good meter like a Fluke and test them after they are charged. you will find as you charge them more they will hold what they are supposed too.

Test them? How?
I don't see how a dvom would be able to tell me capacity???? Even my high dollar fluke can't do that.
I could see voltage but you don't need a fluke for that. LOL..

Terranaut · 04-01-2009, 08:44 AM

Is it possible the charger is inadvertantly set to a 80% storage charge, and not the usual full charge? Some chargers have that feature.

Cheers.

cato · 04-01-2009, 09:14 AM

These pack are not matched and you are not able to Discharge them "EQUALLY" down to Zero (each cell that is) thus the pack will not take the full amount of Mah....simillar to a 20 gal gas tank, if it still has a little gas in it you cannot put a full 20 back into it!! The batteries, as they get older will prob try to take more, plus the peak voltage will go up to compensate for the batteries Internal resistance going up, it is the normal progression of a nmhd life!! Yes you can kill them all the way down, unlike nicds, nmhd don't like to be stoored at Zero; always store with at least a half charge. Have fun

robsdak · 04-01-2009, 12:46 PM

Quote:

Originally Posted by braxx

Test them? How?
I don't see how a dvom would be able to tell me capacity???? Even my high dollar fluke can't do that.
I could see voltage but you don't need a fluke for that. LOL..

well being an electrician, i never rely on just one reading and take it as gospel. it doesn't matter if it is brand new, everything is subject to failure. yes, high dollar Flukes can test for capacity, you just need to know how. if what you are using is dvom, you need a better meter. try getting one that takes an amperage reading aw well. DUH....

braxx · 04-06-2009, 05:55 PM

Quote:

Originally Posted by robsdak

well being an electrician, i never rely on just one reading and take it as gospel. it doesn't matter if it is brand new, everything is subject to failure. yes, high dollar Flukes can test for capacity, you just need to know how. if what you are using is dvom, you need a better meter. try getting one that takes an amperage reading aw well. DUH....

Please tell me how a high dollar fluke can tell me the capacity of my battery packs?
What meter do you suggest that would be better than my Fluke 88 DVOM ?

Duuuuuuuude · 04-06-2009, 06:19 PM

Quote:

Originally Posted by braxx

Please tell me how a high dollar fluke can tell me the capacity of my battery packs?
What meter do you suggest that would be better than my Fluke 88 DVOM ?

Ahhhh...I just figured out what he's getting at. With a known and constant load placed on the battery, you measure output current and the time it takes to drain it. Amps per hour.

Actually, you don't need anything high dollar to do this. A working knowledge of Ohm's or Watt's law, a 12v light bulb, and a basic ohm/volt meter will do fine.

braxx · 04-06-2009, 06:59 PM

Quote:

Originally Posted by Duuuuuuuude

Ahhhh...I just figured out what he's getting at. With a known and constant load placed on the battery, you measure output current and the time it takes to drain it. Amps per hour.

Actually, you don't need anything high dollar to do this. A working knowledge of Ohm's or Watt's law, a 12v light bulb, and a basic ohm/volt meter will do fine.

He made it sound as if it were as simple as checking voltage or the like.
There appears to be no real simple and accurate way to know the exact capacity of a battery. You would have to monitor current input till fully charged or monitor discharge at a constant rate and time it.
You can also tell how much amperage went in by multiplying the charge amperage by the amount of time it takes to peak. That is if the charge current stayed constant.

Duuuuuuuude · 04-06-2009, 07:14 PM

Quote:

Originally Posted by braxx

He made it sound as if it were as simple as checking voltage or the like.

Yeah, I was thinking the same thing...and trying to find out what magic meter he has...

bob1961 · 04-06-2009, 07:25 PM

yeah they show what mah was put in from the charge....if you use a light bulb system to totaly discharge the batteries then charge them they will take more then the 1500 rating then..............bob

....

Chris_The_Battery_Man · 04-07-2009, 12:16 AM

What brand are they? All good cells will peak a few 100 mah past their capacity. Just because it ways 1500... doesnt mean it's limited to that in a charge. I know there was a bad batch of Elite 1500's recently. They're great cells. Just had a bad batch.

bob1961 · 04-07-2009, 05:05 AM

hope the 50 pack of elite 1500's i just bought from you over the weekend isn't one of those batches

....one of the 8 cell packs i made from them charged to 1845 mah on the first charge at .2 A

................bob

....

03-30-2009, 08:30 PM	#1
braxx Newbie Join Date: Feb 2009 Location: Dearborn Heights Posts: 27	NEW 1500mAh batteries only charging up to 1200mAh I bought 4 new 1500mAh NIMH battery packs and a new Onyx 240 charger. I charged all of the packs. I ran all of the packs down and recharged them again and when they finished charging the charger displayed their capacities as: 1355mAh , 1204mAh , 1200mAh and 1112mAh Does the Onyx charger display the amount of charge that went in or does it display the total capacity of the battery? Ie; are these batteries not up to there rating? SORRY I FORGOT TO SAY THESE ARE 2/3A NIMH. Last edited by braxx; 03-30-2009 at 08:45 PM.

03-30-2009, 08:36 PM	#2
robbio4422 Rock Crawler Join Date: Nov 2008 Location: kansas city Posts: 692	im kinda new to lipo but ima take guess here.... im thinking that you are running your batteries on a lipo cut off... the cut off prevents you from draining the battery completely... the 1200+ that your charger is reading to you could be what the battery is getting back. from 1500mah. your useing 1200+ and thats what your putting back in. could be wrong

03-30-2009, 08:49 PM	#3
P1choco Quarry Creeper Join Date: Jan 2009 Location: El Cajon San Diego Posts: 417	Might just be what it put in.

03-30-2009, 08:55 PM	#4
Harvo I wanna be Dave Join Date: Mar 2008 Location: In the Dark Edges of your Mind Posts: 6,386	I have an Onyx charger. It tells you what it put in. You don't drain your batteries to zero so the number will always be different and usually lower than 1500. Don't run your nimh batteries all the way down!

03-30-2009, 08:56 PM	#5
robsdak Pebble Pounder Join Date: Jan 2009 Location: Crestview Posts: 166	how many time have you charged them? the first charge should have been 10% of the capacity. it takes several cycles to get a full charge. i have a couple Team Orion 3000mAh that will charge to 3700mAh. but i was told at the time i bought them, they would hold more. this is just as far as i have pushed them.

03-30-2009, 09:14 PM	#6
braxx Newbie Join Date: Feb 2009 Location: Dearborn Heights Posts: 27	This was only my 2nd charge on them. I'm happy if that is the amount of charge put into them.

03-30-2009, 09:19 PM	#7
Duuuuuuuude Suck it up! Join Date: Mar 2008 Location: Arkansas Posts: 11,652	It shows how many mah's it put in, not how much it has total.

03-30-2009, 09:24 PM	#8
robsdak Pebble Pounder Join Date: Jan 2009 Location: Crestview Posts: 166	get yourself a good meter like a Fluke and test them after they are charged. you will find as you charge them more they will hold what they are supposed too.

04-01-2009, 08:44 AM	#11
Terranaut Quarry Creeper Join Date: Sep 2008 Location: Kuala Lumpur, Malaysia Posts: 372	Is it possible the charger is inadvertantly set to a 80% storage charge, and not the usual full charge? Some chargers have that feature. Cheers.

04-01-2009, 09:14 AM	#12
cato RCC Addict Join Date: Sep 2007 Location: WHEAT RIDGE, CO Posts: 1,102	These pack are not matched and you are not able to Discharge them "EQUALLY" down to Zero (each cell that is) thus the pack will not take the full amount of Mah....simillar to a 20 gal gas tank, if it still has a little gas in it you cannot put a full 20 back into it!! The batteries, as they get older will prob try to take more, plus the peak voltage will go up to compensate for the batteries Internal resistance going up, it is the normal progression of a nmhd life!! Yes you can kill them all the way down, unlike nicds, nmhd don't like to be stoored at Zero; always store with at least a half charge. Have fun

04-06-2009, 07:25 PM	#18
bob1961 I wanna be Dave Join Date: Mar 2008 Location: Wayne county. PA Posts: 2,507	yeah they show what mah was put in from the charge....if you use a light bulb system to totaly discharge the batteries then charge them they will take more then the 1500 rating then..............bob ....

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04-07-2009, 12:16 AM	#19
Chris_The_Battery_Man I wanna be Dave Join Date: Oct 2006 Location: Milwaukie OR Posts: 2,078	What brand are they? All good cells will peak a few 100 mah past their capacity. Just because it ways 1500... doesnt mean it's limited to that in a charge. I know there was a bad batch of Elite 1500's recently. They're great cells. Just had a bad batch.

04-07-2009, 05:05 AM	#20
bob1961 I wanna be Dave Join Date: Mar 2008 Location: Wayne county. PA Posts: 2,507	hope the 50 pack of elite 1500's i just bought from you over the weekend isn't one of those batches ....one of the 8 cell packs i made from them charged to 1845 mah on the first charge at .2 A ................bob ....

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