Charged battery shelf life?

[Nin01]

I work away from home for 4weeks at a time.
I want to know whats the best way to store the batteries i have?

i have;

3s 5000mha 11.1v lipo x2 (traxxas)
2s 4500mha 7.4v lipo
7s 3000mha 8.4v Nimh x2 (traxxas)

should i leave discharged or fully charge them before i go ?

[Jimmie Neutron]

LiPo's should never be left fully charged for more than 48 hours... they should be put to storage voltage at 3.85v/cell.

I have always fully charged my NiMh when storing them... if they self discharge themselves too far down the pack will be ruined.

I have had a set of 3S batteries that I only use for speed runs in the fridge at storage voltage for 8 months or so.