Author Topic: charging a 8.4v nimh pp3 battery  (Read 1662 times)

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Offline m3vuvTopic starter

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charging a 8.4v nimh pp3 battery
« on: December 03, 2020, 10:47:15 am »
Hi all,its a simple question but im struggling to find answers to it,i have a mimh 170mah pp3 type rechargable battery in my multimeter that needs charging,ive  lost my charger but have a lab psu cc+cv,i know its ok to charge it at 10/c but what voltage,the battery is marked 8.4v,cheers m3vuv.
 

Offline tunk

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Re: charging a 8.4v nimh pp3 battery
« Reply #1 on: December 03, 2020, 11:13:41 am »
If you go to https://lygte-info.dk you'll see that
a fully charged NiMh is 1.4-1.5V per cell, so I
guess 10V would be ok.
 

Offline Dabbot

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Re: charging a 8.4v nimh pp3 battery
« Reply #2 on: December 03, 2020, 11:13:54 am »
Set voltage to 9.8V, current to 17mA and charge for 15 hours.
 

Offline Zero999

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Re: charging a 8.4v nimh pp3 battery
« Reply #3 on: December 03, 2020, 05:43:50 pm »
If the battery is marked as 8.4V, then it has it has 7 cells: 1.2V per cell. To fully charge it, the voltage needs to go up to 1.5V per cell, so you need an open circuit voltage of 7*1.5 = 10.5V.

It's generally safer to charge at a low, rather than high current. Set the voltage to 10.5V, the current to 9mA and charge for 24 hours.
 

Offline james_s

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Re: charging a 8.4v nimh pp3 battery
« Reply #4 on: December 03, 2020, 05:49:32 pm »
As long as the current is limited, the voltage can be higher and it won't matter, the battery will determine the voltage.
 

Offline m3vuvTopic starter

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Re: charging a 8.4v nimh pp3 battery
« Reply #5 on: December 03, 2020, 05:51:36 pm »
thanks all.
 


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