Chinese Lithium ..
Chinese Lithium batteries -- all the same --
I have taken apart a few of these Li-Ion batteries, and they are all the same construction - and seems to be made in China by the same manufacturer, and just given different color plastic "tops"
3 of these batteries had the same plastic extrusion marks, so even though they were labeled with different manufacturers and had different color, they were the same battery.
I took them apart because they failed in some way or other, most common is that one or more cells collapse because of too deep a discharge of the battery.
Some of the higher capacity (5 Ah real capacity) were built with 2,5 Ah cells directly parallel connected, which means they are in a state of "forced balancing" - if one of the parallel cells die the other one dies as well, and the risk of a fire is increased greatly :surprise:
Most of the cheaper chinese Li-ion batteries are made with flat "pouch type" Li-ion cells, which is not a bad thing in itself, but sometimes the cells take up only a fraction of the actual volume of the battery case, and any swelling of the cells, which indicates a bad cell, and can be a cause of the cell igniting, can not be seen.
Such a fire cost an importer of Boss Hoss Bikes and Trikes to loose 3 big block Bikes in a lorry fire. ---- :violin:
The red Li-ion battery shown in the photo is exactly the type I've taken apart, I bet it has a "test" button on top with 3 or 4 blue LED's to show battery charge ... Some of them work just fine, I have one on my lawnmower that has run 3 seasons now, and is only on a charger in winter.
I've built my own Battery for my F4, using quality flat pouch cells of 6Ah REAL capacity, with a BMS circuit and a balancing charger. Parts for this can be bought on the web, from webshops specializing in batteries for Drones and model aircraft. It WILL be more expensive, but the battery can be charged correctly, and you can keep an eye on the balancing, and replace a faulty cell.
I realize this is not for anyone unfamiliar with basic electronics, so I would advise buying quality , known brands of Li-ion batteries for your MV .. Just imagine the grief, if it quietly catches fire in your garage ,,,,,,,, :-( because you choose to save 30% on the battery ...:toothless