US 12,334,759 B2
Battery string state of charge balancing with phase sharing
Jun-mo Kang, Ann Arbor, MI (US); Charles W. Wampler, II, Birmingham, MI (US); and Dave G. Rich, Sterling Heights, MI (US)
Assigned to GM GLOBAL TECHNOLOGY OPERATIONS LLC, Detroit, MI (US)
Filed by GM GLOBAL TECHNOLOGY OPERATIONS LLC, Detroit, MI (US)
Filed on Dec. 2, 2021, as Appl. No. 17/541,097.
Prior Publication US 2023/0179000 A1, Jun. 8, 2023
Int. Cl. H02J 7/00 (2006.01); B60L 58/22 (2019.01); H01M 10/44 (2006.01)
CPC H02J 7/0014 (2013.01) [B60L 58/22 (2019.02); H02J 7/0024 (2013.01); H02J 7/0048 (2020.01); H01M 10/441 (2013.01)] 20 Claims
OG exemplary drawing
 
1. A battery system comprising:
a first positive terminal;
a second positive terminal;
a negative terminal;
switches;
first, second and third battery modules, wherein each of the first, second, and third battery modules includes three strings of battery cells that are configured to, at different times be:
connected in series and to the first positive terminal via first ones of the switches;
connected in parallel and to the second positive terminal via second ones of the switches; and
disconnected from both of the first and second positive terminals; and
a switch control module configured to:
determine state of charges (SOCs) of the strings of battery cells, respectively;
determine, using model predictive control, periods of phases, respectively, to balance SOCs of the first, second, and third battery modules;
determine, using model predictive control, periods for the strings, respectively, including setting one of the periods for one of the strings to be included in at least two of the phases;
selectively actuate the switches based on the periods of the phases and the periods for the strings of battery cells,
wherein the switch control module is configured to:
during a first phase:
connect the strings of battery cells of the first battery module in series and to the first positive terminal; and
connect the strings of battery cells of the second and third battery modules in a parallel mode and to the second positive terminal;
during a second phase:
connect the strings of battery cells of the first and third battery modules connected in parallel and to the second positive terminal; and
connect the strings of battery cells of the second battery module in series and to the first positive terminal; and
during a third phase:
connect the strings of battery cells of the first and second battery modules in parallel and to the second positive terminal; and
connect the strings of battery cells of the third battery module in series and to the first positive terminal.