This very interesting article was linkesd on Endless-Sphere. Basically. The Hailong case was only designed for 48v (65 cells). To get 70 vells in for 52v, the assemblers throw away the cell holding/spacing arrangement and bodge the cells in, which brings safety and reliability issues. If you want 52v, it's probably best to avoid a Hailong case.
52 Volt Battery Proceed With Caution
52 volt batteries have become popular, but are they really living up to the hype? Are they safe? We sold 52 volt batteries for about 1 year because of the constant customer requests, this is what we learned and why we no longer advise using them. 1- 60% of 52 volt packs we sold had failures...
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