This wasn't an issue until the most recent update...TU-211197, but my small batteries are overheating within 2 cycle even though I have them built in a snow biome, near 2 wheezeworts and the only power draw from them is two lights and the novice research center. It started too early in the game to have any technology to even combat them overheating, I had to deconstruct and reconstruct them since the dupes are wasting all my start of the game metal repairing them. As you can see they are vented, and not put right next to each other but the temperature continues to rise.
Steps to Reproduce
Start a new game and place small batteries
This issue has not been confirmed by a developer yet.