Charge control apparatus, charge pattern creating device, method, non-transitory computer readable medium and power storage system
A charge control apparatus according to an embodiment controls charge of a secondary battery to be charged, on the basis of a charge pattern which is calculated from inner state parameters of the secondary battery to be charged, and of a deterioration model or deterioration map of a secondary battery. The charge control apparatus updates the charge pattern on the basis of change of the inner state parameters.
1. A charge pattern creating device estimating an inner state parameter of a first battery to be charged and calculating a charge pattern for the first battery based on an estimation value of the inner state parameter of the first battery, the charge pattern creating device comprising:
a battery characteristic estimator configured to estimate the estimation value of the inner state parameter of the first battery based on data on current and voltage of the first battery measured during charge or discharge of the first battery; and
a charge pattern calculator configured to calculate the charge pattern for the first battery based on a first reference data and a specified value of a first deterioration speed of the first battery, wherein
the first reference data is reference data considered to correspond to the first battery from the reference data indicating at least a relationship among a second deterioration speed of a secondary battery, one or more reference parameters related to the secondary battery, and a charge current of the secondary battery, wherein the first reference data includes (i) second reference data at least indicating a first relationship among the second deterioration speed of a positive electrode of the secondary battery, the one or more of the reference parameters, and a second upper limit of the positive electrode and (ii) third reference data at least indicating a second relationship among the second deterioration speed of a negative electrode of the secondary battery, the one or more of the reference parameters, and a third upper limit of the charge current in the negative electrode; and
the charge pattern indicates a value of the charge current corresponding to a first reference parameter which is one of the reference parameters.
2. The charge pattern creating device according to claim 1 , further comprising:
an upper-limit data calculator configured to calculate first upper limit data indicating relationship between the first reference parameter and a first upper limit value of the charge current for obtaining the first deterioration speed equal to or lower than the specified value, based on the first reference data and the specified value of the first deterioration speed, wherein
the charge pattern calculator calculates the charge pattern based on the first upper limit data.
3. The charge pattern creating device according to claim 2 , wherein
the upper-limit data calculator calculates:
second upper limit data indicating relationship between the first reference parameter and the second upper limit of the charge current for obtaining the second deterioration speed of the positive electrode equal to or lower than the specified value, and
third upper limit data indicating relationship between the first reference parameter and the third upper limit for obtaining the second deterioration speed of the negative electrode equal to or lower than the specified value, and the charge pattern calculator calculates the first upper limit data based on the second upper limit data and the third upper limit data.
4. The charge pattern creating device according to claim 3 , wherein
the first upper limit is lower than smaller one of the second upper limit and the third upper limit.
5. The charge pattern creating device according to claim 1 , wherein
in the charge pattern, a period in which the charge current is supplied is formed of a plurality of sections in which the value of the charge current is constant.
6. The charge pattern creating device according to claim 1 , wherein
the first reference parameter is the voltage of the first battery.
7. The charge pattern creating device according to claim 1 , wherein
the battery characteristic estimator estimates an estimation value of a battery characteristic based on the inner state parameters, and
necessity of change of the value of the charge current is determined based on the estimation value of the battery characteristic.
8. The charge pattern creating device according to claim 7 , wherein
the battery characteristic estimator calculates, as the inner state parameters, respective initial charge amounts and masses of the positive electrode and the negative electrode of the first battery, calculates a battery capacity or an open circuit voltage as the battery characteristic, and regards the calculated values as the estimation values.
9. The charge pattern creating device according to claim 1 , further comprising a reference data acquirer configured to acquire the first reference data based on the estimation value.
10. A charge control apparatus comprising:
a charge/discharge controller configured to control charge and discharge of the first battery;
a measurer configured to measure voltage and current of the first battery in charge or discharge of the first battery; and
the charge pattern creating device according to claim 1 .
11. The charge control apparatus according to claim 10 , wherein
the charge/discharge controller performs charge of the first battery based on the charge pattern calculated by the charge pattern creating device.
12. A method for estimating an inner state parameter of a first battery to be charged and calculating a charge pattern for the first battery based on an estimation value of the inner state parameter of the first battery, the method comprising:
estimating the estimation value of the inner state parameter of the first battery based on data on current and voltage of the first battery measured during charge or discharge of the first battery; and
calculating the charge pattern for the first battery based on a first reference data and a specified value of a first deterioration speed of the first battery, wherein
the first reference data is reference data considered to correspond to the first battery from the reference data indicating at least a relationship among a second deterioration speed of a secondary battery, one or more reference parameters related to the secondary battery, and a charge current of the secondary battery, wherein the first reference data includes (i) second reference data at least indicating a first relationship among the second deterioration speed of a positive electrode of the secondary battery, the one or more of the reference parameters, and a second upper limit of the positive electrode and (ii) third reference data at least indicating a second relationship among the second deterioration speed of a negative electrode of the secondary battery, the one or more of the reference parameters, and a third upper limit of the charge current in the negative electrode; and
the charge pattern indicates a value of the charge current corresponding to a first reference parameter which is one of the reference parameters.
13. A non-transitory computer readable medium storing a program for estimating an inner state parameter of a first battery to be charged and calculating a charge pattern for the first battery based on an estimation value of the inner state parameter of the first battery, the program causing a computer to execute:
estimating the estimation value of the inner state parameter of the first battery based on data on current and voltage of the first battery measured during charge or discharge of the first battery; and
calculating the charge pattern for the first battery based on a first reference data and a specified value of a first deterioration speed of the first battery, wherein
the first reference data is reference data considered to correspond to the first battery from the reference data indicating at least a relationship among a second deterioration speed of a secondary battery, one or more reference parameters related to the secondary battery, and a charge current of the secondary battery, wherein the first reference data includes (i) second reference data at least indicating a first relationship among the second deterioration speed of a positive electrode of the secondary battery, the one or more of the reference parameters, and a second upper limit of the positive electrode and (ii) third reference data at least indicating a second relationship among the second deterioration speed of a negative electrode of the secondary battery, the one or more of the reference parameters, and a third upper limit of the charge current in the negative electrode; and
the charge pattern indicates a value of the charge current corresponding to a first reference parameter which is one of the reference parameters.
14. A power storage system comprising:
a first battery to be charged; and
a charge control apparatus configured to charge the first battery, wherein
the charge control apparatus includes:
a battery characteristic estimator configured to estimate an estimation value of an inner state parameter of the first battery based on data on current and voltage of the first battery measured during charge or discharge of the first battery, and
a charge pattern calculator configured to calculate a charge pattern for the first battery based on a first reference data and a specified value of a first deterioration speed of the first battery, wherein
the first reference data is reference data considered to correspond to the first battery from the reference data indicating at least a relationship among a second deterioration speed of a secondary battery, one or more reference parameters related to the secondary battery, and a charge current of the secondary battery, wherein the first reference data includes (i) second reference data at least indicating a first relationship among the second deterioration speed of a positive electrode of the secondary battery, the one or more of the reference parameters, and a second upper limit of the positive electrode and (ii) third reference data at least indicating a second relationship among the second deterioration speed of a negative electrode of the secondary battery, the one or more of the reference parameters, and a third upper limit of the charge current in the negative electrode,
the charge pattern indicates a value of the charge current corresponding to a first reference parameter which is one of the reference parameters; and
the first battery is charged along the charge pattern.