Battery cabinet power attenuation

Three aging modes of battery are quantified by the established OCV model. The semi-empirical models are proposed for three aging modes. The model of aging modes on ohmic/polarization resistance is established. Remaining useful life and SOH are predicted by proposed models and particle filter.

A L A M i, E L A M i, z L A M i represent the pre-exponential factor, activation energy, and power factor of LAM i, respectively. According to Ref., the capacity loss of lithium-ion batteries can be described as a linear combination of LLI and LAM. Therefore, the loss capacity Q loss is defined as Eq. (27).

Charge-discharge cycles are not the only cause of capacity decay, as storing lithium batteries at high temperatures can also cause capacity decay. A fully charged lithium-ion battery can lose 35% of its capacity when stored at 40 ° C (104°F) for a year without use.

The aging mode of the battery is quantified by the capacity ratio of electrodes and the SOC bias of the positive electrode. To better understand the variation of internal parameters with battery aging, the simplified electrochemical model is used to identify the parameters in Ref. .

In the beginning, the loss of delithiated material in the negative electrode only has a weak effect on the battery capacity, because the negative electrode has excessive active substances, and the OCV curve of the negative electrode remains unchanged at the low SOC stage.

To identify the aging mechanism of the battery by using the OCV curve of electrodes, it is necessary to establish the correlation model between the aging and the OCV curves. Besides, considering that the SOC i of the electrode can not be measured directly, it is necessary to map the SOC of the whole battery to the electrode SOC i.