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FIG. 4. a) Tafel plot for a coupled-ion electron transfer reaction relative to the overpotential for a NMC532 model at different states of charge, which gives rise to different differential conductance behavior as well as reduction current fraction in the next two plots. b) Differential resistance values for a NMC532 model captured at different overpotentials for various states of charge are plotted. Specifically, pulses at 5, 20, and 100 mV overpotentials are plotted at the red points. c) Reduction current fraction is plotted with respect to different overpotentials. State of charge variation plays a minimal role in the reduction current fraction, causing reduction current fractions at different SOC values to overlap. We plot the reduction current fraction values for pulse experiments at 5, 20, and 100 mV overpotentials with red points. d) Kinetic fraction of surface blockage is plotted at different state of charge values for varying overpotentials.

Figure 4 a) Tafel plot for a coupled-ion electron transfer reaction relative to the overpotential for a NMC532 model at different states of charge, which gives rise to different differential conductance behavior as well as reduction current fraction in the next two plots. b) Differential resistance values for a NMC532 model captured at different overpotentials for various states of charge are plotted. Specifically, pulses at 5, 20, and 100 mV overpotentials are plotted at the red points. c) Reduction current fraction is plotted with respect to different overpotentials. State of charge variation plays a minimal role in the reduction current fraction, causing reduction current fractions at different SOC values to overlap. We plot the reduction current fraction values for pulse experiments at 5, 20, and 100 mV overpotentials with red points. d) Kinetic fraction of surface blockage is plotted at different state of charge values for varying overpotentials.

Related Figures (7)

FIG. 1. a) A comparison of the physical description of pulsing and resting in a battery cell, where lithium ions in the electrolyte are purple and battery particles are blue. b) Voltage response tc a current pulse and c) current response to a voltage pulse and the effects of degradation on ¢ pulse measurement in an industry-standard HPPC measurement are shown, with the pulse and rest sections displayed.
FIG. 1. a) A comparison of the physical description of pulsing and resting in a battery cell, where lithium ions in the electrolyte are purple and battery particles are blue. b) Voltage response tc a current pulse and c) current response to a voltage pulse and the effects of degradation on ¢ pulse measurement in an industry-standard HPPC measurement are shown, with the pulse and rest sections displayed.
FIG. 2. Goodness-of-fit results for the linear approximation and the exact calculation of the fitnes: W for each degradation mechanism in a full cell NMC532-graphite cell for a 100 mV (dis)chargs pulse are shown at various states of degradation, from least to most degraded at a cathode state o charge of 0.8 and anode state of charge of 0.4. The effects of film resistance on the (a) cathode anc (d) anode, the surface blockage of the (b) cathode and (e) anode, and the electrolyte concentratior loss are plotted for this cell at values close to the initial nondegraded state.
FIG. 2. Goodness-of-fit results for the linear approximation and the exact calculation of the fitnes: W for each degradation mechanism in a full cell NMC532-graphite cell for a 100 mV (dis)chargs pulse are shown at various states of degradation, from least to most degraded at a cathode state o charge of 0.8 and anode state of charge of 0.4. The effects of film resistance on the (a) cathode anc (d) anode, the surface blockage of the (b) cathode and (e) anode, and the electrolyte concentratior loss are plotted for this cell at values close to the initial nondegraded state.
FIG. 3. HPPC simulation shown for a single pulse size, with six different values of state of charge co where the pulses are performed, with slow charges between the different state of charge values. The pulse experiments are repeated for each pulse value. The pulses are performed using the protocol in Algorithm 1.
FIG. 3. HPPC simulation shown for a single pulse size, with six different values of state of charge co where the pulses are performed, with slow charges between the different state of charge values. The pulse experiments are repeated for each pulse value. The pulses are performed using the protocol in Algorithm 1.
FIG. 5. Sensitivity analysis of each degradation mechanisms on the fitness W for a NMC532. graphite cell for a 100mV (dis)charge voltage pulse or for a 1C (dis)charge current pulse at < cathode state of charge of 0.8 and anode state of charge of 0.4. The effects of film resistance fo: (a) the cathode, (b) the surface blockage for the cathode, (c) the electrolyte concentration, (d) the film resistance for the anode, and (e) the surface blockage of the anode are plotted for this cell fo1 values close to the initial degradation state.
FIG. 5. Sensitivity analysis of each degradation mechanisms on the fitness W for a NMC532. graphite cell for a 100mV (dis)charge voltage pulse or for a 1C (dis)charge current pulse at < cathode state of charge of 0.8 and anode state of charge of 0.4. The effects of film resistance fo: (a) the cathode, (b) the surface blockage for the cathode, (c) the electrolyte concentration, (d) the film resistance for the anode, and (e) the surface blockage of the anode are plotted for this cell fo1 values close to the initial degradation state.
FIG. 6. Comparison of fitting linearized or exact objective functions to simulated results fo1 full cell simulation for NMC532-graphite at ten different degradation points for each degradation mechanism for voltage/current pulse HPPC is shown. (a,d) are the film resistance mechanisms for the cathode and anode; (b,e) are the surface blockage mechanisms for the cathode and anode, and (c) is the electrolyte loss mechanism.
FIG. 6. Comparison of fitting linearized or exact objective functions to simulated results fo1 full cell simulation for NMC532-graphite at ten different degradation points for each degradation mechanism for voltage/current pulse HPPC is shown. (a,d) are the film resistance mechanisms for the cathode and anode; (b,e) are the surface blockage mechanisms for the cathode and anode, and (c) is the electrolyte loss mechanism.
Appendix B: Full Cell Simulation Parameters
Appendix B: Full Cell Simulation Parameters
FIG. 7. Comparison of fitting linearized objective function to exact results for full cell NMC532. graphite simulation at nine different degradation points for a combined set of simulations witl all degradation mechanisms present. (a,d) are the film resistance mechanisms for the cathod« and anode, (b,e) are the surface blockage mechanisms for the cathode and anode, and (c) is the electrolyte loss mechanism.
FIG. 7. Comparison of fitting linearized objective function to exact results for full cell NMC532. graphite simulation at nine different degradation points for a combined set of simulations witl all degradation mechanisms present. (a,d) are the film resistance mechanisms for the cathod« and anode, (b,e) are the surface blockage mechanisms for the cathode and anode, and (c) is the electrolyte loss mechanism.
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