Celticmg. The issue you had was likely not a design flaw but a manufacturing issue where parts were assembled with enough variance in tolerance to cause a failure at the extreme. Think of it like two overly simplified cases..you can have a rod and a hole. As it would be simply too expensive to machine everything to exact +/- 0.000 tolerances, you make the hole on the + side and the rod on the - side then the two of them will always fit. The problem comes when the hole is at the top end of the + side and the rod is at the bottom end of the - side, the two will fit but they will be rather sloppy.
Now think of this with a set of electronics. You can have a whole load of parts that are all within their individual tolerance, but when combined, the resulting circuits are enough out of whack to have issues when they are pushed to the extreme. So a battery circuit board that might test fine, and work perfectly fine in California and Florida, might fail in Upper Michigan when it gets really cold. The exact same part design except with a different set of components with better-matched tolerances will work perfectly fine. It's like me saying that since my iMac is a bit of a lemon and seems to get quite a few issues, that ALL iMac or even all mac products, in general, must be bad or at least won't work in Canada. That would be a vast jump.