The Low self discharge NiMh AA Cells such as Eneloop or Panasonic Infinium are probably the way to go.



For AA NiMh cells the iSun BattPak is a useful addition. It works as a Battery Charger designed to work directly with portable Solar PV panels such as a Silva II portable 4W panel shown above (it also works well with a 25W folding solar PV panel). Once charged the BattPak will then function as a portable power pack via its own Cigarette car type 12V connection. The Battpak can also be charged using a regular AC-DC supply or suitable DC supply such as SLA or lead acid car battery. There are bound to lots of working lead acid car batteries in non working vehicles available after an earthquake. A small 12V DC-DC switching regulator could also prove to be very useful.

Primary Lithium such as Energiser and Ultralife are pretty specialist cells, they are pretty much unsurpassed (at the moment) for portability i.e. low weight, excellent cold temperature operation, long life and storage lifetime. They are expensive but $20-30 worth of Energisers AAs could prove to be invaluable in the next 10-20 years. Keep some alkalines around as well, just so you are not tempted to open the packets Enerliser Lithiums if the TV remote needs feeding.