ZOP Power 3s lipo 5000mah 60c battery dropped to 8.6v

So I know these batteries are the cheapest of the cheapest and probably are 1/2 of what they claim to be rated at but I thought I would get more than 1 full charge before the battery died but hey this is what I get for buying shit. This is just a warning new people who want to save money on batteries. DON’T!. I used the last of my tax return to build a cheap esk8 for under $480AUD and I was literally left with $3. Clearly I wasted $70AUD on these and am left with a heavy ass longboard. Not really I bought a complete longboard in case this exact thing happened so I do have normal longboard wheels and trucks. just $400 out of pocket. my%20esk8-3%20(2) I had checked my batteries and both were at 11.4v. I only made it ~ 500m before the esc started beeping so I pushed back home and checked my batteries and one had dropped to 11.3v and the other was at 8.6v.

I used my lipo cell battery tester and 2 of the 3 cells are at 2.85v so I assume it isn’t a great idea to try revive it considering its just a junk battery to begin with.

Or should I try and contact the seller and see if they send a replacement?

Your batteries where at storage charge 11.4 Full charge is 12.6v for a 3 cell pack You should have fully balanced charged them to 12.6 before using them.

When i got the batteries I fully balanced charged them to 12.6. I went for a ride came back and charged them fully. Next day I went for a ride, came back and went out again a few hours later without charging them which is when this happened.

what charger are you using and did you charge them separately?

Using the IMAXB6. Its one of those $30 ones and yes they were charged separately. I had the battery in one of those parallel charging boards but because my charger only did a max of 6A I charged them individually with only 1 battery connected at a time. The charger was set on LIPO balance charge for a 3s at 5000mah

You may have gotten a pack with one or more bad cells right out of the box. This happened to me once when purchasing Zippy Lipos from HK. I ordered 4 packs and 2 of them where bad.

Thats what I thought. The dimentions of both batterys are different one is about 3mm thicker and you can see the cells through the heat shrink on one of the batteries

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The battery which the cells are covered by the tape or whatever is used under the heat shrink is the one that dropped voltage. The battery that you can see the cells is about 3mm thicker than the other and has been since I received them.

Whenever I buy Lipos, I check the internal resistance before charging them the first time. If one or more cells have a significantly high internal resistance, it is a bad pack. for example 5 milliohms per cell or less is good. I have bought Turnigy Lipos that where as low as 2 milliohms per cell.