Re: Hot battery, what's the problem?
Its natural, but .....<br /><br />A battery will heat up when you charge it because of the chemical reaction you are causing by pumping new electrons in. A battery will also heat up when you discharge it because of the reverse chemical reaction. Those two are just as normal as can be. The problem is that the battery should be of such a size that the reacted chemicals and materials they are reacting with (battery acid, anodes and diodes) are a small portion of the total battery, thus the rise of temperature will be slight. If you are seeing extreme heat, and if you can feel it go ahead and consider it to be extreme, one of two thing is going on. The first is easy to understand, that is that the battery is too small for the load you are placing on it. If that were the case this would have been happening since the battery was new. The second is that the effective size of the battery has been reduced, which happens as the battery ages. Simply put as they get older less and less of the internal material is available for the chemical reactions to work on. There is another possibility too of course. That is that very dirty contacts between the battery and the starter will cause make it harder to provide the requisite energy to crank the engine and as a consequence the battery could heat up a bit I guess.<br /><br />At any rate the solution here is just like most other electrical problems. First get out there with a little bit of sand paper and a wire brush and clean ever contact in sight. Clean the battery terminals and the cable terminals that attach to them. Inspect the cables for corrosion and replace as necessary or cut them back if possible for new fittings to be added. In no case use any cable that shows the dreaded "Black Wire". Green is almost as bad as Black. If you still have the problem after doing that then a replacement battery may be in order.<br /><br />Of course there is one other thing as well. If something is causing the engine to require considerably more effort to crank it over than in the past this will result in a more robust drain on the battery as well, and that will cause additonal heat. So, is the engine starting to seize up? Is the starter haning up? <br /><br />Those are about the only real possibilitys that come immediately to mind.<br /><br />Thom
