The embodiments of the present disclosure disclose a method for data transmission, comprising: authenticating, by a target node in a battery management system, a source node in response to a request for data transmission from the source node; selecting, by the target node, any two prime numbers from a pre-stored set of prime numbers if the authentication is passed, generating a public key and a private key according to the two prime numbers, and transmitting the public key to the source node; performing, by the source node, a first encryption byte-by-byte for source data to be transmitted using the public key, performing a second encryption for the first encrypted data using a first encryption algorithm stored by the source node itself, and transmitting the second encrypted data to the target node.