A novel parameter for evaluation on power performance of Ni–MH rechargeable batteries

In the work, two novel conceptions of “capacity quality” (CQ) and “capacity quality coefficient” (λ) were defined to evaluate cycling power capabilities of Ni–MH rechargeable batteries when considering the effect of the kinetic limitation. For convenient comparison, the capacity quality coefficient (λ) and the efficiency of charge/discharge (η) were in parallel applied to characterize cycling capabilities based on the data from BYD H-3/4AAA800 Ni–MH batteries at 1C–3.5C. The results show that there is an obvious difference between λ and η which served as evaluation indexes for rechargeable batteries, and that the secondary battery with good capacity quality also has a good cycling capability and rate capability, especially at high rate. The introduced capacity quality not only subtly covered kinetic information of the rechargeable batteries but also factually reflected stability of the electrode materials.