I was part of a group of people that decided to attempt to use some ThunderSky LiIon cells for our electric vehicles. Since they have to be shipped from China, we wanted to do a large order to reduce shipping costs.

I purchased Qty 52 of their 90AH cells, part # TS-LP90.

This turned out to be a poor choice.

When we received them, some of the cells already had some rust on their steel terminals.

Initial testing showed that the 90AH cells would be lucky to make 70AH capacity.

We’ve also discovered that they need to be HOT to work properly, up around 40 deg C seems about what they need. Of course, it’s not too difficult to heat them, since they have a rather high internal resistance, and come up to that temperature fairly quickly with only a 18A load.

They are rated at a max current of 3C (or 270A for these 90AH cells). As far as I can tell they can’t reach that without falling below their minimum cell voltage.

I have lots of data collected testing a working with these cells. Several have died in only 20 – 30 cycles of use.

We did contact ThunderSky Corp about the problems with them not meeting their rated specs.

So far, they aren’t interested in having happy customers.

So, to Summarize:

TS-LP90AH cell, rated at 90AH.

1. 70-80 AH capacity, but only when quite warm.
2. 10-20 AH if they aren’t warm.
3. Hi internal resistance, so they heat up with only a 18A draw. Likely to overheat quickly at higher draws.
4. NO CUSTOMER SUPPORT WHATSOEVER
5. Not a chance of meeting their rated max output current.
6. Can only charge slowly (20A or so max). Some cells overheat quickly above that rate, some just won’t accept higher rates without going over voltage.
7. Wildly inconsistent quality control. Cells vary by quite a bit.