Battery management system, and methods for address allocation and offline reconnection

1 . An address allocation method in a battery management system including a main battery management unit and N sub-battery management units, where N is greater than or equal to 1 and the main battery management unit is connected with the N sub-battery management units through a single bus, comprising:

powering the battery management system on;

calculating a local identification code in each of the N sub-battery management units;

selecting one of the N sub-battery management units through an I/O line using the main battery management unit;

broadcasting an address allocation message from the main battery management unit, wherein the address allocation message comprises an address number and an identification code;

receiving the address allocation message at the one of the N sub-battery management units, and when the one of the N sub-battery management units is selected, the one of the N sub-battery management units judges whether the identification code of the address allocation message is identical to the local identification code of the one of the N sub-battery management units:

when the identification code of the address allocation message is identical to the local identification code of the one of the N sub-battery management units, entering a normal communication state;

when the identification code of the address allocation message is different from the local identification code of the one of the N sub-battery management units, saving the address number of the address allocation message, and sending the local identification code of the one of the N sub-battery management units to the main battery management unit;

abandoning the address allocation message when (i) the one of the N sub-battery management units is not selected and there is no connection timeout in the one of the N sub-battery management units, or (ii) the identification code of the address allocation message is not consistent with the local identification code;

when the connection timeout has not occurred, the one of the N sub battery management units also judges whether the identification code of the address allocation message is consistent with or identical to the local identification code, then:

when the identification code of the address allocation message is consistent with or identical to the local identification code, entering the normal communication state, and marking a corresponding I/O line fault; and

when the identification code of the address allocation message is not consistent with or identical to the local identification code, sending a first pairing request message from the one of the N sub battery management units to the main battery management unit, wherein the first pairing request message includes the local identification code;

receiving the first pairing request message and/or the local identification code in the main battery management unit, and searching whether there is a corresponding record in a record sequence;

when the corresponding record is in the record sequence, sending a second pairing message with a recorded sequence position number as an address; and

when the corresponding record is not in the record sequence, adding or replacing an unused position or location number as the address, and sending a third pairing message with the unused position or location number as the address.

2 . The address allocation method according to claim 1 , wherein the local identification code is a 16-bit numerical value.

3 . The address allocation method according to claim 2 , wherein the local identification code is calculated by CRC from a unique ID of each of the N sub battery management units.

4 . The battery management system according to claim 3 , wherein the addresses are not repeated.

5 . The address allocation method according to claim 2 , where N is greater than or equal to 4.

6 . A battery management system, comprising a main battery management unit and N sub-battery management units, wherein N is greater than or equal to 1; the main battery management unit is connected with the N sub-battery management units through a CAN bus, and each of the N sub-battery management units adopts the address allocation method according to claim 1 , so that the main battery management unit allocates a corresponding address to each of the N sub-battery management units.

7 . The battery management system according to claim 6 , where N is greater than or equal to 3.

8 . The battery management system according to claim 6 , comprising a CAN network with the addresses therein, wherein the battery management system automatically allocates the addresses.

9 . The address allocation method according to claim 1 , wherein the address is for the one of the N sub battery management units.

10 . The battery management system according to claim 9 , where N is greater than or equal to 4.

11 . The address allocation method according to claim 1 , where N is greater than or equal to 3.

12 . The battery management system according to claim 11 , wherein the addresses correspond to actual physical locations.

13 . The address allocation method according to claim 1 , further comprising:

after the one of the N sub-battery management units receives the third pairing message, when the one of the N sub-battery management units is selected and the third pairing message includes an identification code that is identical to the local identification code, entering normal communication.

14 . An offline reconnection method, comprising performing the address allocation method according to claim 1 , and monitoring a connection state of the N sub-battery management units in real time using the battery management system, wherein the address allocation method re-allocates the address until the one of the N sub-battery management units is connected when the connection state of the one of the N sub battery management units is offline.

15 . The address allocation method according to claim 1 , wherein the one of the N sub battery management units has an IO port, and judges whether it is selected by detecting an enable signal at the IO port.

16 . The address allocation method according to claim 1 , wherein the connection timeout occurs when a time spent connecting the one of the N sub battery management units exceeds a preset time.

17 . The address allocation method according to claim 1 , further comprising monitoring a connection status of the N sub-battery management units in real time.

18 . The address allocation method according to claim 17 , wherein when the first one of the N sub-battery management units is offline, the address allocation method re-allocates the address until the first one of the N sub-battery management units is connected.

19 . The address allocation method according to claim 1 , wherein the unused position or location number is in a sequence.

20 . The address allocation method according to claim 1 , wherein the main battery management unit generates an address setting enable signal and broadcasts the address allocation message; and the main battery management unit allocates addresses to the N sub-battery management units in sequence.