Anything that improves reliability, lifecycle cost, and efficiency will be appreciated. The battery maintenance overhead for existing electric vehicles is considerable (cooling systems, heating systems, power shifting). Sometimes they seem to have a mind of their own if you stand next to them when they are parked.
It is difficult to have technology advancement in battery so even a small step ahead indeed is very encouraging. A123 did a great job by extending the battery life even at high temperature. Even if cost of the battery is lowered much, this can help the whole industry (and the EV industry) a lot by replacing battery packs less frequently. Again if cooling system can be cut down, the cost of the whole system is reduced. More is that the total reliability can even be improved by fewer components!
Marketerspeak for "it's expensive" coupled with the use the word COULD: "reducing or eliminating the need for a thermal management system could reduce “total cost of ownership” over the life of a battery", In a larger system, the cooling/heating system is a fraction of the system cost. Clearly this battery tech is a loser, IMO, if it can't bring costs down, doesn't last with temperature cycling (mysteriously missing), or if it doesn't carry more Wh/kg. Tax boondoggle it looks like to me.
Sounds promising - hope there is a follow-up story on the results of the -30C testing. A twenty per cent increase at -30 is oddly phrased as current Lithium secondary battery technolgy doesn't have any meaningful capacity at -30.