I forgot the question was about weight increase during charging...
Zinc-Air cells are dominant in hearing aids, but are single-use.
Lithium-air are rechargable and should achieve 2-3 times the energy density of sealed Lithium-ion cells. https://en.m.wikipedia.org/wiki/Lithium_air_battery
@Emyr started
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I forgot the question was about weight increase during charging...
Zinc-Air cells are dominant in hearing aids, but are single-use.
Lithium-air are rechargable and should achieve 2-3 times the energy density of sealed Lithium-ion cells. https://en.m.wikipedia.org/wiki/Lithium_air_battery