- I think it was around last Christmas time and bored with it all I ordered up a supposed 68,000mAh 36v battery for ...... wait for it ..... £28 inc p&p
- Now, I had no idea what I'd get for the money but I knew that I would NOT get anything other than complete rubbish, but (a) I was curious and bored with winter, and (b) the physical size/form factor appealed as it would fit into the side pocket of one of my Carradice saddle bags.
- 2 months later it arrived but I didn't get to load test it until April time and when I did I got a whole 1,500mAh out of it.
- So after another boring few days, I eventually dissected the beast to see what cr*p was inside and actually I really quite liked the way it'd been constructed, with some obvious shortcomings like the lack of any physical impact protection as the only wrapping was the blue shrink wrap - just bits of foam on the corners but no other protection from dropping etc.
- However, the batteries where in holders and the only wires where the two for the XT60 connector. All the balance wires where in the main baseboard in a layered sandwich construction with of course the batteries interconnected with nickel strip (I didn't measure the thickness or test if steel coated or pure - durgh, but I doubt at that price point that it was pure nickel and probably only 0.1mm).
- The BMS - looked to me to barely minimal. It was same port charging but no means of switching off power. TBH I was suprised to even see bleed resistors for balancing (simple top balancing I guess?).
- During one discharge test I inadvertantly let them discharge below my normal test voltage of 3.0v per cell and they went down to 2 point something - so clearly no meaningful LVC on the BMS.
- The cells - no idea - no labelling!
- Anyway, I liked the form factor and physical layout of the batteries and I'm considering a similar construction method for a 10s2p build of my own.
- Below are some pics for those amongst the more curious readers - any comments/observations?
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