Canon batteries

[Dave Hassell]

Does anyone know why Canon batteries should be stored in a discharged state and does it cause any damage to them?
The manuals for both the 50D and 7D say that ‘Storing the battery after it is fully charged can lower the battery’s performance’.
Dave Hassell.

[Christopher C.M. Cooke]

All my batteries are stored in a fully charged state and always have been though some charge may be lost during long periods of non use.

[Dave Hassell]

Hello Chris,
I have always done the same - recharged before storage, but I am wondering why Canon say don't store them fully charged.
Dave Hassell.

[Christopher C.M. Cooke]

Dave if Canon suggests that, they probably want to sell us more batteries.:)

I have NEVER had a Canon battry die on me in many years and the newer ones seem to go on forever.

[John Chardine]

General Li-Ion battery advice should be applicable to modern Canon batteries. This article is quite useful.

http://www.batteryuniversity.com/parttwo-34.htm

It mentions batteries should be stored at about 40% charge. Worst case apparently is to store them full charged in a hot location.

[Dave Hassell]

Thanks a lot John. The article is very useful and explains Canon's advice. It has also shown that I am using my laptop battery incorrectly!

Many thanks,

Dave.

[Christopher C.M. Cooke]

Quite right John no battery should be stored in hot locations, thanks for the link.

[Roger Clark]

John,
Thanks! That is VERY useful info.
Roger