Why is it bad to mix battery brands together?
To all practical extent, there is no problem with mixing brands as long as you stay with the same size and type of battery. I mix brands as well and have never had any issues. I think the various brands simply want you to buy their battery. This makes sense. If you have a couple of their batteries already and are told not to mix brands, this means you’ll buy the same brand again. The technical aspect, as I understand it, is that the different brands may not discharge equally. If one battery, because it’s a different brand and drains quicker it may get a reverse voltage across it from the other, higher charged batteries. This could cause shorter battery life in the other batteries and even possibly (very, very remotely) damage whatever device they’re in because of this. As I said, I mix brands and don’t worry about it and have never had any issues that could be attributed to doing so.
