Method for use with a vehicle battery pack having a number of individual battery cells
First Claim
Patent Images
1. A method for use with a vehicle battery pack having a plurality of battery cells, comprising the steps of:
- (a) determining a state of charge for the vehicle battery pack (SOCPack), wherein the state of charge (SOCPack) corresponds to when the vehicle is ‘
on’ and
generally does not include effects due to diffusion voltage, hysteresis voltage or both;
(b) determining a terminal voltage for at least one of the vehicle battery pack (VPack) or the plurality of battery cells (VCell), wherein the terminal voltage (VPack) or (VCell) corresponds to when the vehicle is ‘
off’ and
generally does include effects due to diffusion voltage, hysteresis voltage or both; and
(c) using the state of charge (SOCPack) and the at least one terminal voltage (VPack) or (VCell) to determine an average transient voltage effect for the plurality of battery cells.
8 Assignments
0 Petitions
Accused Products
Abstract
A system and method for use with a vehicle battery pack having a number of individual battery cells, such as a lithium-ion battery commonly used in hybrid electric vehicles. In one embodiment, the method evaluates individual battery cells within a vehicle battery pack in order to obtain accurate estimates regarding their average transient voltage effect, open circuit voltage (OCVCell) and/or state of charge (SOCCell) so that a cell balancing process can be performed. These cell evaluations may be performed fairly soon after the vehicle is turned off and in a manner that utilizes a minimal amount of in-vehicle resources.
49 Citations
20 Claims
-
1. A method for use with a vehicle battery pack having a plurality of battery cells, comprising the steps of:
-
(a) determining a state of charge for the vehicle battery pack (SOCPack), wherein the state of charge (SOCPack) corresponds to when the vehicle is ‘
on’ and
generally does not include effects due to diffusion voltage, hysteresis voltage or both;(b) determining a terminal voltage for at least one of the vehicle battery pack (VPack) or the plurality of battery cells (VCell), wherein the terminal voltage (VPack) or (VCell) corresponds to when the vehicle is ‘
off’ and
generally does include effects due to diffusion voltage, hysteresis voltage or both; and(c) using the state of charge (SOCPack) and the at least one terminal voltage (VPack) or (VCell) to determine an average transient voltage effect for the plurality of battery cells. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10)
-
-
11. A method for use with a vehicle battery pack having a plurality of battery cells, comprising the steps of:
-
(a) determining a first vehicle battery parameter when the vehicle is ‘
on’
;(b) determining a second vehicle battery parameter when the vehicle is off, wherein the second vehicle battery parameter is determined after the expiration of a turn-off period; (c) using the first and second vehicle battery parameters to develop a virtual cell model that is a reference for the plurality of battery cells; and (d) using the virtual cell model to estimate a state of charge (SOCCell) for each of the plurality of battery cells, wherein in-vehicle resources are used to develop the virtual cell model in step (c) and estimate the (SOCCell) in step (d). - View Dependent Claims (12, 13, 14, 15, 16, 17, 18, 19, 20)
-
Specification