US 2025/0147105 A1 · SECONDARY BATTERY STATE OF HEALTH ESTIMATION METHOD, SECONDARY BATTERY STATE OF HEALTH ESTIMATION PROGRAM, AND SECONDARY BATTERY STATE OF HEALTH ESTIMATION APPARATUS

Abstract

In a secondary battery state of health estimation method, which estimates the state of health (SOH) of a secondary battery by use of a Weibull law, the total capacity retention rate of the secondary battery, obtained from at least one of data on the secondary battery in operation and a cycle test, is separated into a float capacity retention rate ascribed to deterioration dependent on a use period, and a cycle capacity retention rate ascribed to deterioration dependent on the number of charges/discharges; Weibull coefficients mf, ηf corresponding to the float capacity retention rate, and the float capacity retention rate represented by the following formula (1) are obtained; Weibull coefficients mc, ηc corresponding to the cycle capacity retention rate, and the cycle capacity retention rate represented by the following formula (2) are obtained; and the state of health in a period t or at a cycle number N is estimated from the following formula (A): [ Equation ⁢ 1 ]  Float ⁢ capacity ⁢ retention ⁢ rate = exp ⁢ { - ( t η f ) m f } ( 1 ) Cycle ⁢ capacity ⁢ retention ⁢ rate = exp ⁢ { - ( N η c ) m c } ( 2 ) State ⁢ of ⁢ health ⁢ ( SOH ) = exp ⁢ { - ( t η f ) m f } × exp ⁢ { - ( N η c ) m c } ( A )

Claims11

Dependent claims

A secondary battery state of health estimation method, which estimates a state of health (SOH) of a secondary battery by use of a Weibull law, comprising:

separating a total capacity retention rate of the secondary battery, obtained from at least one of data on the secondary battery in operation and a cycle test, into a float capacity retention rate ascribed to deterioration dependent on a use period, and a cycle capacity retention rate ascribed to deterioration dependent on a number of charges/discharges;
obtaining Weibull coefficients mf, ηf corresponding to the float capacity retention rate, and the float capacity retention rate represented by the following formula (1);
obtaining Weibull coefficients mc, ηc corresponding to the cycle capacity retention rate, and the cycle capacity retention rate represented by the following formula (2);
and
estimating the state of health in a period t or at a cycle number N from the following formula (A):
[
Equation
⁢
1
]

Float
⁢
capacity
⁢
retention
⁢
rate
=
exp
⁢
{
-
(
t
η
f
)
m
f
}
(
1
)
Cycle
⁢
capacity
⁢
retention
⁢
rate
=
exp
⁢
{
-
(
N
η
c
)
m
c
}
(
2
)
State
⁢
of
⁢
health
⁢
(
SOH
)
=
exp
⁢
{
-
(
t
η
f
)
m
f
}
×
exp
⁢
{
-
(
N
η
c
)
m
c
}
(
A
)

92 more elements

Dependencies are inferred from the claim text.

Secondary battery state of health estimation method, secondary battery state of health estimation program, and secondary battery state of health estimation apparatus

Life of this patent

Secondary battery state of health estimation method, secondary battery state of health estimation program, and secondary battery state of health estimation apparatus

Life of this patent

Abstract

Claims11