Method and device for updating battery pack SOH of charging and battery swap station

Abstract

The invention provides a method for updating battery pack SOH of a charging and battery swap station. The method comprises the steps that a to-be-tested battery pack sends an SOH updating instructionto a master controller; the master controller sends a maintenance instruction to the to-be-tested battery pack; the to-be-tested battery pack starts a discharge mode so that each single battery pack starts to discharge at a preset first current threshold; the discharge voltage of each single battery pack is acquired, and discharging is stopped when one discharge voltage is smaller than a preset voltage threshold value; a charging mode is started after a first time threshold value is preset so that each single battery is charged at a preset second current threshold value; a charging voltage value of each single battery pack is acquired, and charging is stopped when the highest charging voltage value in the single battery pack is greater than a preset second voltage threshold; and an actualcharging capacity is determined according to the charging time and a charging current, and the SOH is updated according to the actual charging capacity. According to the method, the SOH precision is improved, and a difference between a display endurance mileage and an actual endurance mileage is reduced.

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 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. 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 est...

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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