The evaluation of the cycle life of batteries is an essential task in the assessment of the reliability and cost of battery-operated devices. Several compact cycle life models have been proposed in the literature, that exhibit a general trade-off between generality and accuracy. Some models are based on a compact equation derived from experimental data and try to extract a general relationship between cycle life and the relevant parameters (mostly the depth of discharge), but suffer from poor accuracy. At the other extreme, more accurate models, based on incorporating the aging effect into an equivalent circuit, tend to be focused on a specific device and are seldom applicable to another battery.In this work we propose an equation-based model that tries to overcome the accuracy limits of previous similar models. The model parameters are obtained by fitting the curve based on information reported in datasheets, and can be adapted (with different accuracy levels) to the amount of available information.We applied the model to various commercial batteries for which full information on their cycle life is available. Results show an average estimation error, in terms of the number of cycles, generally smaller than 10%, which is consistent with the typical tolerance provided in the datasheets, and much lower than previous equation-based models.

The aging of a rechargeable battery is mainly due to stress during charge-discharge cycles. Although the discharge phase is difficult to control, the charging phase can be performed in a specific way in order to mitigate the aging of the battery during its usage. It therefore becomes important to select the correct charging algorithm. In the case of mobile systems, equipped mainly with lithiumion batteries, the standard widely adopted for charging a battery is the typical constant current/constant voltage (CC-CV) protocol usually based on a linearly regular charge process. In this work, we propose a charging protocol based on the standard CC-CV method in which the charge start time and the value of the charging current can be programmed in such a way that the aging of the battery is mitigated. To validate this charging scheme we use an aging model that includes the charge/discharge current among the major parameters, and an analytical macro-model for the CC-CV charge time analysis.

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