Hi,
I recently bought a Bluetti EB55 that advertises a capacity of 537Wh; the deal is on OzB somewhere. Long story short I got some smart plugs and tested the capacity by charging it full, then running it flat via the smart plug. It recorded an output of only 375Wh (70% of stated capacity).
What would be an acceptable real world value for capacity?
And, is there any better tests I can do to determine real capacity?
Thanks
hi
i have an ecoflow river2. it's built in inverter is inefficient.
maybe same in your case
out of is 256w
i get about 200w when used via dc
The capacity of a battery is dependent on the discharge rate. High discharge rates reduce the effective capacity. Low discharge rates increase the effective capacity. Bluetti would have rated the EB55s capacity at some specified discharge rate. Typically car batteries are rated at C10, which is the discharge rate that would fully discharge the battery in 10 hours. So try it with about a 50W load and see if you think the result indicates a claimed capacity of 537Wh is honest or an exaggeration.
The advertising department has dyslexia.
and never seen nor used these "power" stations.
Think of the EcoFlow team as well …
Aren’t the capacity values based on the total capacity of the cells but the cut off voltage is designed to protect the battery of cells from over-discharging so the useable capacity is around 70-80%?
Volts make sense. Cheers
Aren’t the capacity values based on the total capacity of the cells but the cut off voltage is designed to protect the battery of cells from over-discharging so the useable capacity is around 70-80%?
I don't think that's the case.
I've tested loads of new cells when I was doing hobbyist battery stuff- either lithiums or nickle cells. Discharged gently, they'd report pretty much bang on their rated capacities. e.g. if I test new Enerloops where the cutoff is (iirc) 1V, I'd expect more than 1900mAh for the standard white cells.
100 MegaWatts