Battery overheating

[oldbilbo]

While passing, I dropped into the UK/Europe distribution centre for Yuasa batteries, and spoke with a 'tech specialist'. Among the 'snippets' I picked up was this one...

....Regarding temperature, as a rule of thumb, the service life of a lead-acid battery is reduced by half for every 10°C increment above the recommended 20°C operating temperature....

Now, what I know about batteries can be typed into a YBW 'Post new thread' window more than a couple of times - and still leave space - but I'd not come across that concern before. I guess there will be quite a few of us whose batteries are in compartments near the engines, where the temperature routinely soars above 20°C and stays there.

I guess we need to learn a little more about this....

 

[Plevier]

That applies more to batteries in long life standby applications where corrosion is the killer. Like all chemical reactions, it happens a lot faster with increasing temperature.
In a boat situation, where cycle life is more likely the limit, temperature will still have an effect but rather less. I wouldn't like to quantify it.
It is important that charging voltage is reduced at higher temperatures (and increased at lower temperatures or you won't get full charge) but your charger should look after that. However if the temperature sensing is at the charger, and the battery is mounted somewhere much warmer, the charger won't know and will overcharge. This has been a problem on cars too and some now have temperature sensing in the battery compartment.
Also with cars, because lots of people find their battery is dead with the first frost, they assume it's the frost that has killed it. It isn't, the deterioration has happened over the summer, the frost just shows it up because of the increased starter current requirement.