US Patent 8738309 Battery pack maintenance for electric vehicles

A method of repairing a used battery pack from an electric vehicle include removing the battery pack from the vehicle. Battery tests are performed on at least some of the plurality of batteries and a battery test result for each of the batteries tested are obtained and stored in a database. A plurality of replacement batteries are tested and test results for each of the replacement batteries are stored in the database. The battery test results from the database are retrieved and used to create a refurbished battery pack. An apparatus includes a database for storing test results.