Comment by m463
2 days ago
> a round-trip efficiency of 96 percent
Doesn't matter for cars, but I think that's pretty good/important for grid storage.
2 days ago
> a round-trip efficiency of 96 percent
Doesn't matter for cars, but I think that's pretty good/important for grid storage.
Lithium batteries in cars are usually at least that good already. Most of the efficiency lost is in converting back and forth between AC/DC between the grid and the motors, and the rest in the auxillary features such as heating and cooling the cabin.
sorry, probably should have quoted the entire thing:
> The batteries are showing a round-trip efficiency of 96 percent, a significant 2 to 3 percent better than LFP. (“Round trip” refers to the amount of energy a battery discharges, relative to the amount used to charge it).
I think for cars, the efficiency probably doesn't matter that much. If it costs $1.03 per kwh instead of $1.00 per kwh, or 103 miles vs 100 miles, no car owner will care.
But grid storage is all about efficiency.
> But grid storage is all about efficiency.
Is it? Isn't there usually a very large price ratio between when grid batteries are charged and discharged? Like charging at 5 cents and discharging at 25? In that situation a couple percent of inefficiency is nothing special, just a small cost.
Series hybrid cars which do fuel->electricity->motion are unacceptably inefficient and flopped at sales. Will sodium make them viable? My reckless googling says LFP batteries in vehicles has roundtrip efficiency of 80% and sodium has 95%.