Optimal Battery Charging for Damage Mitigation

Hartley, Tom T.; Lorenzo, Carl F.

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NASA NTRS · 20030112593

Optimal Battery Charging for Damage Mitigation

Hartley, Tom T.·Lorenzo, Carl F.

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Abstract

Our control philosophy is to charge the NiH2 cell in such a way that the damage incurred during the charging period is minimized, thus extending its cycle life. This requires nonlinear dynamic model of NiH2 cell and a damage rate model. We must do this first. This control philosophy is generally considered damage mitigating control or life-extending control. This presentation covers how NiH2 cells function, electrode behavior, an essentialized model, damage mechanisms for NiH2 batteries, battery continuum damage modeling, and battery life models. The presentation includes graphs and a chart illustrating how charging a NiH2 battery with different voltages and currents affects damages the battery and affects its life. The presentation concludes with diagrams of control system architectures for tracking battery recharging.

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Hartley, Tom T., Lorenzo, Carl F.. 2003-04-01. Optimal Battery Charging for Damage Mitigation. https://ntrs.nasa.gov/citations/20030112593

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