Meh, we already have non-lithium battery tech that is better than all Li variants for energy-per-unit volume density.
Lithium just needs to get us through the next 10 years of energy-per-unit weight criteria.
As Malthusian dooms go, peak lithium is not even in my top 20.
Sodium-ion batteries, yeah, thats gonna take a while until they solve the lowish energy density and low charge-discharge cycle capacity. 10 years seems reasonable.