A battery that’s safer and cheaper than lithium-ion while offering comparable energy density? That sounds like a pipe dream. But such a battery is in fact in the works, using a chemistry of renewables to store over 220 Wh/kg. Singaporean startup Flint believes it has the formula for the most sustainable battery the world has ever seen, capable of replacing lithium for applications like EV power and grid storage. Maybe that is a dream. Or maybe it’s the revolutionary eco-optimized battery of the near-future.

A fully sustainable paper battery that can be recycled and dropped in compost at the end of its life cycle sounds too good to be true. It kicks off a major cynicism alert, and the questions flow like water through a burst dam.

Does it offer such low capacity as to be useless for anything outside a laboratory? No, Flint estimates energy density at 226 Wh/kg, which falls comfortably within the range of existing lithium tech.