Well, the truth is, who knows what the next big thing will be after lithium-ion battery will be, but there are a number of companies working to find out.
Currently, the lithium-ion battery is the best chemistry we have in rechargeable battery technology, but what is “best?” Well, there are a few criteria, which make the lithium-ion battery the go-to chemistry for practically every portable electronic device, from smartphones to electric vehicles. First, energy density needs to be high, packing the most watt-hours per kilogram (Wh/kg) possible. Second, the battery must be able to cycle hundreds of times without degrading significantly. It also needs to be safe, as illustrated by some lithium-ion battery fires in Boeing and Tesla Motors products. Finally, it needs to be cheap.
Frankly, getting all three of these in the same package is difficult but, at least for now, the lithium-ion battery is the best we have available. The lithium-ion battery cells used in the Tesla Model S, for example, are rated at ≈200 Wh/kg and can be cycled ≈800 times. A recent development by Envia Systems seemed promising, whose battery holds 400 Wh/kg, but which lost about 50% capacity by 450 cycles. A recent lithium-sulfur battery developed by Lawrence Berkeley National Laboratory may be able to hold 800-1200 Wh/kg, but can only be cycled a dozen times.
Sakti3’s solid-state thin-film battery may hold one part of the solution, as its solid electrolyte can’t leak, isn’t flammable, and is far lighter than current lithium-ion battery designs. Johnson Controls and DOW Kokam are working on Nickel-Manganese-Cobalt Oxide (NiMaCoO or NMC) batteries, which could be much cheaper than current battery technologies. Magnesium-Ion (Ma-Ion) batteries should also be cheap and have decent energy density, and they’re also non-flammable. Perhaps one of the best breakthroughs could be Power Plus Japan’s new dual-carbon battery, which is cheap, and charges about 20x faster. There’s plenty of work to do, but until the “next big thing” comes along, the lithium-ion battery reigns supreme in portable energy storage systems.
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