The specs on the listing are:
1. Rated continual discharge current : 43A
2. Max continual discharge current : 50A
3. Pulse discharge current : 70A
4. Capacity : 20Ah
Hi Ben,
I've been doing some research on that particular battery and I think it is highly unlikely to match the above specifications stated by the supplier.
If you check out
this post on Endless-Sphere you can find more information about it.
Even if it has the stated cells, it will not have the stated capacity, as there is physically not enough room within those dimensions to accomodate the required number of cells, even without the
BMS unit!
I tried various layouts using my CAD package but could only manage to fit around 108 cells maximum in the same sized space, and ~13 of those would have to be left out to allow room the
BMS to fit inside:
Unless the physical dimensions are larger than the ones quoted, I reckon they will have used 91 cells
(13 series sets of 7 paralleled cells).
If the cells are the stated 2.2Ah cells, this would only produce a maximum capacity of 15.4Ah instead of the stated 20Ah.
You can't have a capacity of 20Ah using 2.2Ah cells, it would either be 19.8Ah for 13S9P or 22Ah for 13S10P, but there definitely isn't room for 117 or 130 cells in that size package.
If your charger's voltage is marked as 54.6V, it will definitely be a 13S pack, but if it is marked as 58.8V it will be a 14S pack.
If it's a 14S pack, it will probably only have 6 cells in parallel blocks and the total capacity would then be just 13.2Ah, unless they have somehow managed to squeeze 98 cells
and the
BMS unit inside the stated dimensions, but I don't think that is very likely.
My biggest concern would be if they had used cheaper low power output cells instead of the stated "Samsung inr18650-22P 5C 10A high drain cells or LG 5C 10A high drain cells". If this was the case, the voltage would sag noticeably under heavy load and the pack could get very warm as a result.
Weaker cells do not appreciate having to work too hard and would be more prone to early failure, resulting in a greatly reduced battery lifespan.
I'd like to be able to say that the battery you received will meet all of the specifications stated by the seller, but I feel this is highly unlikely.
Alan 
