Battery pack health degree estimation method and device

Abstract

The invention discloses a battery pack health degree estimation method and device. The method comprises steps that health degree index change of each storage unit of a battery pack in a charging or discharging process is detected; according to the detected health degree index change, whether the storage unit has a correction opportunity in a charge state within the pre-determined health degree estimation time segment is determined; a charge state value of the storage unit having two or more correction opportunities after correction is calculated, and one-or-more-times accumulative capacity change of the storage unit having two or more correction opportunities during accumulative capacity change between every two correction opportunities is calculated; a first estimation health degree of the storage unit having two or more correction opportunities is acquired according to the data acquired previously, and a health degree of the battery pack is estimated according to the first estimation health degree of the storage unit having two or more correction opportunities. The method is advantaged in that the health degree of the battery pack can be accurately estimated.

Description

technical field [0001] The invention belongs to the technical field of battery packs, and in particular relates to a method and device for estimating the health degree of a battery pack. Background technique [0002] Because the battery pack will age or deteriorate after long-term use, it is necessary to estimate the state of health (State-of-Health, SOH) of the battery pack, also known as the life state, and some are also called aging, deterioration degree or backward battery pack, literature There are different names in Chinese and Chinese, but the meaning is basically the same. Among them, estimating the health degree of the battery pack based on the cumulative change of the battery pack capacity is generally represented by SOHC. The prior art has the following problems in the estimation of the SOHC of the battery pack: [0003] On the one hand, in an electrical system powered by a battery pack, for example, during normal use of an electric vehicle. The electrical syste...

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Problems solved by technology

The electrical system powered by the battery pack lacks the opportunity to accurately calculate the above-mentioned health of the battery pack

[0004] On the other hand, due to the inconsistency of the state of charge (State of Charge, SOC) of different power storage units in the battery pack, it is difficult to locate the specific power storage unit

[0005] On the other hand, due to the inconsistency in the aging process of each storage unit in the battery pack, the overall health of the battery pack cannot reflect the actual aging state of each storage unit.

[0006] Based on the above problems, it is difficult to obtain a more accurate battery pack SOHC estimation method for the SOHC of the battery pack in the prior art.

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