The problem that no one really talks about is the Achilles’ heel of the MANPADS — its battery. All MANPADS such as Stinger (FIM-92) and Strella (SA-7) have a shelf life on their batteries. Storage conditions, especially extremes of heat and cold, can severely affect battery life. Without a good battery, your MANPADS is just so much expensive junk. The question that should be asked is how fresh were the batteries supplied with the missiles?
From a technical point of view, couldn’t an external battery with a couple of wires attacted to the internal battery’s contacts work?