A method and device for updating a battery pack SOH in a charging and swapping station

Abstract

The invention provides a method for updating the SOH of a battery pack in a charging and swapping station, comprising: the battery pack to be tested sends an SOH update command to a general controller; the general controller sends a maintenance command to the battery pack to be tested; The battery pack turns on the discharge mode, so that each single battery pack starts to discharge at a preset first current threshold; the discharge voltage of each of the single battery packs is obtained, and when one of the discharge voltages is less than the preset voltage threshold, stop discharging; start the charging mode after preset the first time threshold, so that each of the single cells is charged at the preset second current threshold; obtain the charging voltage value of each of the single battery packs, when the single cells When the highest charging voltage value in the bulk battery pack is greater than the preset second voltage threshold, charging is stopped; the actual charging capacity is determined according to the charging time and the charging current, and the SOH is updated according to the actual charging capacity. This method improves the SOH accuracy and reduces the difference between the displayed cruising range and the actual cruising range.

Description

technical field [0001] The invention relates to the technical field of charging and swapping stations, in particular to a method and device for updating a battery pack SOH in a charging and swapping station. Background technique [0002] New energy pure electric vehicles currently have a common weakness: the estimation of cruising range is inaccurate. For example, the estimated cruising range is 100km, but the actual driving range is only 50km, and they are forced to stop halfway, causing complaints and complaints from customers, which greatly hinders the development of new energy vehicles. promotional application. [0003] The root cause of inaccurate estimation of cruising range is inaccurate estimation of SOC (State of Charge, remaining power), and the main reason for inaccurate estimation of SOC is inaccurate estimation of SOH (state of health, battery health). If a certain method is adopted , control strategy, etc. to improve the SOH estimation accuracy, the SOC estima...

AI Technical Summary

Problems solved by technology

[0002] New energy pure electric vehicles currently have a common weakness: the estimation of cruising range is inaccurate. For example, the estimated cruising range is 100km, but the actual driving distance is only 50km, and they are forced to stop halfway, causing complaints and complaints from customers, which greatly hinders the development of new energy vehicles. Promoted application of

Unable to meet user requirements well

[0008] The actual SOH of the battery is too small due to external reasons (such as loose connection of the poles to the copper bar), which cannot be identified by the current detection method, and will eventually introduce SOH errors, resulting in a further decrease in SOH accuracy

Due to the inconsistent internal polarization and inconsistent attenuation of the battery, the SOH accuracy will be further reduced

[0009] The reduction of SOH accuracy directly affects the discrepancy between the displayed cruising range and the actual cruising range of the vehicle, for example: the displayed cruising range is 100km, but the actual driving range can only be 80km, etc.

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