RV lithium battery decay

How do you describe battery degradation?

Battery degradation can be described using three tiers of detail. Degradation mechanisms describe the physical and chemical changes that have occurred within the cell. Mechanisms are the most detailed viewpoint of degradation but are also typically the most difficult to observe during battery operation.

Why is battery degradation important?

This improves the lifetime economics, enables longer warranties 4 and dilutes the environmental impacts associated with raw material extraction and manufacturing. 9,10 Understanding battery degradation is key to increasing operational lifetime.

Can fatigue crack model predict battery capacity loss?

The fatigue crack model (Paris’ law) has been incorporated into a single particle model for predicting battery capacity loss. 121 Crack propagation is coupled with the SEI formation and growth (diffusion dominant), to account for the loss of lithium inventory.

What is loss of lithium inventory (LLI)?

This mode groups mechanisms which lead to a reduction in the material available for electrochemical activity. Secondly, loss of lithium inventory (LLI) groups mechanisms resulting in a reduction of the amount of cyclable lithium available for transport between electrodes.

What causes power fade in lithium ion ions?

Capacity is irreversibly lost due to otherwise cyclable lithium being trapped within the SEI.33 In addition, the SEI layer is less permeable to Li+ ions than the electrolyte, restricts electrolyte flow through pore blocking and consumes the electrolyte solvent. All of these effects increase the overall impedance of cells, leading to power fade.

What happens if a lithium ne is reduced?

A reduction in the lithium content from the NE will lead to the SoC of that electrode decreasing whilst the PE remains the same. This is known as stoichiometric drift and leads to a reduction in the capacity but also an increase in the PE potential at the end of charge, accelerating the PE degradation mechanisms.