Thunder Power TP820CD charging problem

[Scoobalimalima]

Hi everyone.

I just purchased the TP820CD charger recently and I am having troubles when charging my JR TX battery (only battery I've charged with charger at this stage). The battery is an 8s 1500mAh NiMH 9.6v battery. I have tried charging it several times (out of the TX) and it never charges anywhere near full capacity and my TX goes flat within an hour or two of use. The battery does get warm at the completion of the charge so I'm not sure what the problem is.

Stats are, Discharge set to 0.9v per cell
Delta Peak set to !0mv (was at 5mv)
Charge rate 1C 1.5A
Charge time 13min
Completed charge batt capacity 343mAh
Output voltage 11.22v
Voltage peaks during charge at about 12.1v

Not sure if the battery is stuffed or a problem in the charger settings? I bought the Tx new about 6 months ago. I am looking at getting a Life Tx battery at some stage but still would like to know why I'm only getting a charge of around 340mAh out of my current NiMH battery.

Appreciate any help.

Cheers,

SLL

[RedOctobyr]

Only on my phone, so have to be kinda brief. But basically, you just need to start with some reading on charging NiMH.

1C (1.5A) is much too fast. 1/5C to maybe 1/2C tops is the fastest you want to go.

Leave deltaV at 5mV for now, not 0mV. The lower you set that, the sooner it stops the charge.

Discharging first is a good idea, to help understand what you're putting back, vs rated capacity. I typically use 1V/cell, myself.

You can also just do a slow, "forming" charge. Not a bad idea with a new pack, to help equalize the cells.

For better or worse, NiMH charge very differently than LiPos; I find them trickier to charge, the rules aren't as cut-and-dried as with LiPos.

Sent using Tapatalk.

[Scoobalimalima]

Thanks a lot for the info.

Yes, I probably should of done a bit of research first and read the charger manual entirely before pulling my hair out but your advice has solved my problem.

I changed the charge rate to 300mAh and it gave me a full 1500mAh charge, (I naively assumed that a 1c charge rate was the lowest I could do, before reading the charger manual properly).

Btw, that was a typo last post, I meant 10mv DP not !0mv. I have it set to 8mv now and it seems to do the trick.
Cheers.

SLL


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