Battery management system
A battery management system is provided. According to an embodiment of the present disclosure, the battery management system for managing a battery pack including a plurality of battery modules may include a plurality of individual battery management units respectively corresponding to the plurality of battery modules and a management module configured to integrally manage the plurality of individual battery management units, wherein each of the individual battery management units includes a state-of-health (SOH) calculator to calculate SOH of each of the plurality of battery modules and a state-of-charge (SOC) calculator to calculate SOC of each of the plurality of battery modules, the management module manages a performance state of all of the plurality of battery modules on the basis of the SOH and SOC of each battery module and the SOC of each battery module is corrected by the SOH of each battery module.
1. A battery management system for managing a battery pack including a plurality of battery modules, the battery management system comprising:
a plurality of individual battery management units respectively corresponding to the plurality of battery modules; and
a management processor configured to integrally manage the plurality of individual battery management units,
wherein each of the individual battery management units includes:
a state-of-health (SOH) processor configured to calculate an SOH of each of the plurality of battery modules and a state-of-charge (SOC) processor configured to calculate an SOC of each of the plurality of battery modules;
wherein the management processor is configured to manage a performance state of the plurality of battery modules based on the SOH and SOC of each of the plurality of battery modules, and
the SOC of each of the plurality of battery modules is corrected by the SOH of each of the plurality of battery modules, and
wherein the management processor is configured to determine a most deteriorated battery module among the plurality of battery modules, and manage the performance state of the plurality of battery modules based on the determined most deteriorated battery module,
wherein the SOC of each of the plurality of battery modules is calculated based on a battery circuit model,
wherein the battery circuit model is represented by one capacitor and two resistors,
wherein the SOC processor is configured to calculate an open circuit voltage of each of the plurality of battery modules using the following equation:
V
=
OCV
+
I
·
R
1
+
∫
(
I
C
-
V
RC
RC
)
d
t
wherein V denotes a battery voltage, OCV denotes the open circuit voltage, I denotes a current, R 1 denotes a resistance that varies as a battery deteriorates, C denotes a set capacitance, and R denotes a set resistance.
2. The battery management system of claim 1 , wherein the management processor is configured to set usable capacity of each of the plurality of battery modules based on the SOH and SOC of each of the plurality of battery modules.
3. The battery management system of claim 1 , wherein the SOH of each of the plurality of battery modules is calculated through SOH for battery capacity and SOH for a resistance increase in a battery.
4. The battery management system of claim 1 , wherein a value of the OCV is corrected by an SOH value for battery capacity that is calculated for each of the plurality of battery modules.
5. The battery management system of claim 4 , wherein the SOC of each of the plurality of battery modules is calculated from an SOC-OCV table based on the corrected OCV value.
6. The battery management system of claim 1 , wherein a value of I·R 1 is corrected by an SOH value for a resistance increase in a battery that is calculated for each of the plurality of battery modules.
7. The battery management system of claim 1 , wherein a voltage and an output of each of the plurality of battery modules are predicted from the battery circuit model.
8. A battery management system for managing a battery pack including a plurality of battery modules, the battery management system comprising:
a plurality of individual battery management units respectively corresponding to the plurality of battery modules; and
a management processor configured to integrally manage the plurality of individual battery management units,
wherein each of the individual battery management units includes:
a state-of-health (SOH) processor configured to calculate an SOH of each of the plurality of battery modules and a state-of-charge (SOC) processor configured to calculate an SOC of each of the plurality of battery modules;
wherein the management processor is configured to manage a performance state of the plurality of battery modules based on the SOH and SOC of each of the plurality of battery modules, and
the SOC of each of the plurality of battery modules is corrected by the SOH of each of the plurality of battery modules,
wherein the SOH of each of the plurality of battery modules is calculated through SOH for battery capacity,
wherein the SOH for battery capacity is calculated by the following equation:
SOH
C
=
Capacity_ini
(
1
-
(
e
a
(
1
)
+
a
(
2
)
T
·
t
a
(
3
)
)
)
wherein SOH C denotes SOH for the battery capacity, Capacity_ini denotes the initial battery capacity, t denotes the battery usage time (seconds), T denotes the battery temperature (K), and a(1), a(2), and a(3) denote relation constants.
9. A battery management system for managing a battery pack including a plurality of battery modules, the battery management system comprising:
a plurality of individual battery management units respectively corresponding to the plurality of battery modules; and
a management processor configured to integrally manage the plurality of individual battery management units,
wherein each of the individual battery management units includes:
a state-of-health (SOH) processor configured to calculate an SOH of each of the plurality of battery modules and a state-of-charge (SOC) processor configured to calculate an SOC of each of the plurality of battery modules;
wherein the management processor is configured to manage a performance state of the plurality of battery modules based on the SOH and SOC of each of the plurality of battery modules, and
the SOC of each of the plurality of battery modules is corrected by the SOH of each of the plurality of battery modules,
wherein the SOH of each of the plurality of battery modules is calculated through SOH for a resistance increase in a battery,
wherein the SOH for a resistance increase in a battery is calculated by the following equation:
SOH
R
=
IR_ini
(
1
-
(
e
b
(
1
)
+
b
(
2
)
T
·
t
a
(
3
)
)
)
wherein SOH R denotes the SOH for a resistance increase, IR_ini denotes a product of a resistance and a current in an initial battery state, t denotes a battery usage time (seconds), T denotes the battery temperature (K), and b(1), b(2), and b(3) denote relation constants.