Theory 06/Electrochemistry
Rate Capability Is a Current Ratio
The claim
Battery rate capability is set by the ratio of exchange current density to the diffusion length rather than by electrode thickness alone.
01The mechanism
The achievable current is limited by how fast ions arrive and how fast the interface can accept them; the ratio sets the knee in the rate curve.
02Predictions
- P1Rate knee should track the ratio.
- P2Thicker electrodes with fast kinetics should match thin ones with slow kinetics.
03Refutation
Rate capability tracking thickness would remove the kinetic term.