In a method and system for authenticating a smart battery for charging, the smart battery receives an encrypted random string. The smart battery is operable to provide power to a device. The encrypted random string is generated by a controller of the device by generating a random string and encrypting the random string with an encryption key. The smart battery decrypts the encrypted random string with the encryption key to recover the random string and transfer the random string to the device. The device verifies that the random string is unchanged to authenticate the smart battery for the charging. If the random string has been modified then the smart battery is disabled from the charging.