Form's basic idea is that low round trip efficiency can work as long as it's cheaper enough. They've always had $20/KWh as a notional price but there's already

Form's basic idea is that low round trip efficiency can work as long as it's cheaper enough. They've always had $20/KWh as a notional price but there's already talk of Sodium batteries in China getting near that price point, while having nearly double the round trip efficiency.