How C-rate and internal resistance separate cell voltage curves and reduce RTE.
Cell Losses & Efficiency
How C-rate and internal resistance separate cell voltage curves and reduce RTE.
C-RATE / RTE / I2R
DC round-trip efficiency95.0%
energy lost / cycle5.0%
voltage gap at 50% SoC30mV
I2R heat at 50% SoC0.04W
At rated 0.5Cyear 0: 95.0%toyear 0: 95.0%no aging yet
Charge and discharge voltage separationOCV / loss gap
Efficiency driversI2R / age
main takeawayLosses grow with current squared and resistance.
Chemistry sets the open-circuit voltage shape. C-rate and aging decide how far the real charge and discharge curves pull apart.
I2R loss index1.0x
I2R heat at 50% SoC0.04 W
operating point0.50C / year 0
resistance factor1.00x
curve split30 mV at 50% SoC
DC efficiency by C-rateRTE / current
speed
sweep C-rate to watch the gap breathe. Higher C-rate increases polarization, aging increases internal resistance, and the shaded voltage gap represents DC round-trip loss.
Equipment visualization - sweep C-rate and age to see the shaded voltage gap, I2R heat, and DC round-trip efficiency change.
Equipment visualization - sweep C-rate and age to see the shaded voltage gap, I2R heat, and DC round-trip efficiency change.
About this visualization
How C-rate and internal resistance separate cell voltage curves and reduce RTE. This interactive diagram is part of the BESS.engineer visuals
library — practical, engineering-led explanations of grid-scale battery energy
storage. Use the controls above to explore it, or download a GIF from the
library view.