Ryobi 20 volt 4 amp hour battery pack failure not charging no power output

[sam_sam_sam]

I have this type of failure before but not like this

I was using this battery pack and had run down until it only shows one led lights

Which is suppose mean that it 25% or less

I have done this a few times before and the battery would charge back up but not
this one there is one light on but it will not charge

So I check each bank of cells and got about 3.67 on each bank the batteries are down on charge but not that low

When this has happened before it would not charge but you would have power for a short time when you would push the battery test button and go off

But this one failed weird no output will not charge but you have the battery light on

It has two mosfets which when I have had them not wanting to charge and have low amp output replacing them it would start working correctly again

This time I am not sure if this is the same type of failure or not

Running a battery load testing on each battery bank and see how good these battery are at this point

Then I will decide weather or not to try to repair this battery pack

A new battery pack is about $50.00 each when you can find the twin battery pack deal

[stj]

Re: Ryobi 20 volt 4 amp hour battery pack failure not charging no power output

and the chargers are badly designed!

[sam_sam_sam]

Re: Ryobi 20 volt 4 amp hour battery pack failure not charging no power output

This is true for the most part you have to pay attention to the changer when you first place a battery on it to charge to make sure that it is charging

[sam_sam_sam]

Re: Ryobi 20 volt 4 amp hour battery pack failure not charging no power output

Running a battery load testing on each battery bank and see how good these battery are at this point

Then I will decide weather or not to try to repair this battery pack

Here are the results of bank one of this battery pack
1837.5 amp hour for each cell in this bank ( 2 ) cells a loss off at 4.5% of a new cell
I have gotten 1960 to 2020 on these type of cells before ( not separating battery bank to run test )

I still have four more banks to test

I run the test as follows
Discharge
Recharge
Discharge
Recharge
Discharge final results

Test setup
2.50 volts cutoff for first discharge to see where discharge roll of voltage starts about 3.40 to 3.50 is a little higher than normal results I have seen as low as 3.1 to 3.3 volts

Charge to 4.20
Discharge to 3.00 volts
Charge to 4.20 volts
Discharge to 3.00 volts

[sam_sam_sam]

Re: Ryobi 20 volt 4 amp hour battery pack failure not charging no power output

Here is the test results