Yeah, am sure these the cheap brands don’t have good batteries. But, have found after a year of using them, they are usually good enough. Unless you’re doing something like ice fishing, almost all outdoor activities take about 1-4 hours, and they last about 4-5 hours on a mix of high/medium. Have only run out a couple of times, and that’s because I was lazy and didn’t charge them before going out. Also, the battery type used for almost all these heated devices is the same, 7.4 volts. Have bought a couple pairs of replacements that also work pretty well (and have bought ones with larger storage capacities as well as smaller ones for skiing as I don’t want the extra bulk). The brand of heated socks I’ve tried are the ones recommended online, Snow Deer and Dr Warm.

Snow Deer have better electronics: The main button requires you to hold it down in order to turn it off and on. This is big deal because it’s easy to accidentally press the button when you’re out and about. But, unlike what all the review say, I find them uncomfortable. They have a piece of wiring that runs along the top of the foot that digs in (and have tried two different pairs, same thing. Have returned them both).

Dr. Warm is more comfortable (not perfect, but for hiking, good enough). But the problem is the main button doesn’t require a long press to turn them off, so sometimes, you’ll find they’ve turned off by accident (or more importantly, turned on and you’ve drained the battery). Still, comfort is more important, and there are ways to get around the button issue, so these are the ones I use daily - will keep the batteries unplugged until needed.

And like someone else said, if all else fails, get a nicer brand, one that is $200+.