I came across this blog entry which basically says that, for lead acid batteries, lower temperatures require higher charging voltage. Can anyone please explain why this is true, or point to an authoritative source?
I did ask this question on Chemistry SE a while ago, and those guys seem to be of the opposite opinion: higher temps need higher voltage.
Intuitively I disagree with them and agree with the blog post: lower temps need more power to move molecules around, remove sulphate crystals etc. But I seek a definitive authoritative explanation.