Battery system, vehicle, and battery mounted device

• US 8,704,489 B2
• Filed: 01/20/2009
• Issued: 04/22/2014
• Est. Priority Date: 01/24/2008
• Status: Active Grant

• Current Assignee: Toyota Jidosha Kabushiki Kaisha (Toyota Motor Corporation)
• Original Assignee: Toyota Jidosha Kabushiki Kaisha (Toyota Motor Corporation)
• Inventors: Hamaguchi, Hiroshi, Goto, Satoshi
• Primary Examiner(s): Dunn, Drew A
• Assistant Examiner(s): GRANT, ROBERT J
• Application Number:
  US12/532,204
• Publication Number:
  US 20100085015A1
• Time in Patent Office: 1,918 Days
• Field of Search: 320/134
• US Class Current: 320/134
• CPC Class Codes: H01M 10/0525 Rocking-chair batteries, i.e. batteries with lithium insertion or intercalation in both electrodes; Lithium-ion batteries
• CPC Class Codes: H01M 10/44 Methods for charging or discharging circuits for charging H02J7/00
• CPC Class Codes: H01M 10/484 for measuring electrolyte level, electrolyte density or electrolyte conductivity
• CPC Class Codes: H02J 7/0069 Charging or discharging for charge maintenance, battery initiation or rejuvenation
• CPC Class Codes: Y02E 60/10 Energy storage using batteries
• CPC Class Codes: Y02T 10/70 Energy storage systems for electromobility, e.g. batteries

Abstract

A battery system (SV1) comprises a lithium ion secondary battery (101), charge and discharge control means (S2, S6-S8), and internal resistance detecting means (M1). The charge and discharge control means comprises: mode control means including increasing mode control means (S2) for increasing the internal resistance of the lithium ion secondary battery and decreasing mode control means (S8) for decreasing the internal resistance; and mode selecting means (S6, S7) for selecting the decreasing mode control means (S8) or the increasing mode control means (S2) when a level of the internal resistance is estimated by the internal resistance detecting means.

Claims

1. A battery system comprising:

one or more lithium ion secondary batteries each having a power generating element and an electrolyte being impregnated in the power generating element and containing lithium ions;

charge and discharge control means for controlling charging and discharging of each of the lithium ion secondary batteries; and

internal resistance detecting means for performing at least one of detection and estimation about a level of internal resistance in at least one of the lithium ion secondary batteries;

wherein the charge and discharge control means comprises;

a plurality of mode control means for controlling charging and discharging each of the lithium ion secondary batteries on a predetermined charge and discharge condition, the mode control means including;

increasing mode control means for controlling charging and discharging each of the lithium ion secondary batteries on an increasing charge and discharge condition, the increasing mode control means being configured to increase the internal resistance of each of the lithium ion secondary batteries by continuously repeatedly performing charging and discharging by charge and discharge control; and

decreasing mode control means for controlling charging and discharging each of the lithium ion secondary batteries on a decreasing charge and discharge condition different from the increasing charge and discharge condition, the decreasing mode control means being configured to decrease the internal resistance of each of the lithium ion secondary batteries by continuously repeatedly performing charging and discharging by charge and discharge control;

mode selecting means for selecting one mode control means to be used from the plurality of mode control means,

wherein the mode selecting means is configured;

to select the decreasing mode control means when the internal resistance detecting means detects or estimates that the internal resistance is relatively high; and

to select the increasing mode control means when the internal resistance detecting means detects or estimates that the internal resistance is relatively low, and

wherein the internal resistance detecting means is resistance correlation physical quantity detecting means for estimating a level of the internal resistance based on a resistance correlation physical quality having a correlation with the internal resistance.

8. The battery system according to claim 1, wherein

the power generating element includes a positive electrode plate and a negative electrode plate,

the electrolyte includes a retained electrolyte retained between the positive electrode plate and the negative electrode plate, and

the resistance correlation physical quantity detecting means is a retained electrolyte concentration detecting means for estimating the level of the internal resistance by performing at least one of detection and estimation on a level of a lithium ion concentration of the retained electrolyte having a correlation with the internal resistance.

9. The battery system according to claim 1, wherein

the power generating element includes a positive electrode plate and a negative electrode plate,

each of the lithium ion secondary batteries has a battery case holding the power generating element,

the electrolyte includes:

a retained electrolyte retained between the positive electrode plate and the negative electrolyte plate; and

a stored electrolyte stored between the power generating element and the battery case so as to allow interconnection with the retained electrolyte,

the resistance correlation physical quantity detecting means is a stored electrolyte concentration detecting means for estimating the level of the internal resistance by performing at least one of detection and estimation of a level of the lithium ion concentration of the stored electrolyte having a correlation with the internal resistance.

16. A vehicle in which the battery system according to claim 1 is mounted.

17. A battery mounted device in which the battery system according to claim 1 is mounted.

2. A battery system comprising:

one or more lithium ion secondary batteries each having a power generating element and an electrolyte being impregnated in the power generating element and containing lithium ions;

charge and discharge control means for controlling charging and discharging of each of the lithium ion secondary batteries; and

internal resistance detecting means for performing at least one of detection and estimation about a level of internal resistance in at least one of the lithium ion secondary batteries;

wherein the charge and discharge control means comprises;

a plurality of mode control means for controlling charging and discharging each of the lithium ion secondary batteries on a predetermined charge and discharge condition, the mode control means including;

first mode control means for controlling charging and discharging each of the lithium ion secondary batteries on a first charge and discharge condition; and

second mode control means for controlling charging and discharging each of the lithium ion secondary batteries on a second charge and discharge condition different from the first charge and discharge condition;

mode selecting means for selecting one mode control means to be used from the plurality of mode control means,

wherein

when a comparison is made between a case of discharging each of the lithium ion secondary batteries by the first mode control means and a case of discharging each of the lithium ion secondary batteries by the second mode control means,

a discharge current by the second mode control means is made smaller on a predetermined discharge condition and equal to or smaller on other discharge conditions than a discharge current by the first mode control means, and

the mode selecting means is configured;

to select the second mode control means when the internal resistance detecting means detects or estimates that the internal resistance is relatively high; and

to select the first mode control means when the internal resistance detecting means detects or estimates that the internal resistance is relatively low.

3. The battery system according to claim 2, wherein

the predetermined discharge condition is a discharge condition where a maximum discharge current available by the first mode control means flows.

4. The battery system according to claim 2, wherein

on any one of the predetermined discharge condition and said other discharge conditions,

a discharge current by the second mode control means is made smaller than a discharge current by the first mode control means.

18. The battery system according to claim 2, wherein

the internal resistance detecting means is resistance correlation physical quantity detecting means for estimating a level of the internal resistance based on a resistance correlation physical quantity having a correlation with the internal resistance.

20. The battery system according to claim 18, wherein

the power generating element includes a positive electrode plate and a negative electrode plate,

the electrolyte includes a retained electrolyte retained between the positive electrode plate and the negative electrode plate, and

the resistance correlation physical quantity detecting means is a retained electrolyte concentration detecting means for estimating the level of the internal resistance by performing at least one of detection and estimation on a level of a lithium ion concentration of the retained electrolyte having a correlation with the internal resistance.

5. A battery system comprising:

one or more lithium ion secondary batteries each having a power generating element and an electrolyte being impregnated in the power generating element and containing lithium ions;

charge and discharge control means for controlling charging and discharging of each of the lithium ion secondary batteries; and

internal resistance detecting means for performing at least one of detection and estimation about a level of internal resistance in at least one of the lithium ion secondary batteries;

wherein the charge and discharge control means comprises;

a plurality of mode control means for controlling charging and discharging each of the lithium ion secondary batteries on a predetermined charge and discharge condition, the mode control means including;

first mode control means for controlling charging and discharging each of the lithium ion secondary batteries on a first charge and discharge condition; and

second mode control means for controlling charging and discharging each of the lithium ion secondary batteries on a second charge and discharge condition different from the first charge and discharge condition;

mode selecting means for selecting one mode control means to be used from the plurality of mode control means,

wherein

when a comparison is made between a case of charging each of the lithium ion secondary batteries by the first mode control means and a case of charging each of the lithium ion secondary batteries by the second mode control means,

a charge current by the first mode control means is made smaller in a predetermined charge condition and equal to or smaller in other charge conditions than a charge current by the second mode control means, and

the mode selecting means is configured;

to select the second mode control means when the internal resistance detecting means detects or estimates that the internal resistance is relatively high; and

to select the first mode control means when the internal resistance detecting means detects or estimates that the internal resistance is relatively low.

6. The battery system according to claim 5, wherein

the predetermined charge condition is a charge condition where a maximum charge current available by the second mode control means flows.

7. The battery system according to claim 5, wherein

on any one of the predetermined charge condition and said other charge conditions,

a charge current by the first mode control means is made smaller than a charge current by the second mode control means.

19. The battery system according to claim 5, wherein

the internal resistance detecting means is resistance correlation physical quantity detecting means for estimating a level of the internal resistance based on a resistance correlation physical quantity having a correlation with the internal resistance.

21. The battery system according to claim 19, wherein

the power generating element includes a positive electrode plate and a negative electrode plate,

the electrolyte includes a retained electrolyte retained between the positive electrode plate and the negative electrode plate, and

the resistance correlation physical quantity detecting means is a retained electrolyte concentration detecting means or estimating the level of the internal resistance by performing at least one of detection and estimation on a level of a lithium ion concentration of the retained electrolyte having a correlation with the internal resistance.

10. A battery system comprising:

one or more lithium ion secondary batteries each having a power generating element including a positive electrode plate and a negative electrode plate, an electrolyte containing lithium ions and being impregnated in the power generating element, and a battery case holding the power generating element and the electrolyte; and

charge and discharge control means for controlling charging and discharging of each of the lithium ion secondary batteries,

the electrolyte including;

a retained electrolyte retained between the positive electrode plate and the negative electrode plate; and

a stored electrolyte stored between the power generating element and the battery case so as to allow interconnection with the retained electrolyte, and

stored electrolyte concentration detecting means for performing at least one of detection and estimation on a level of the lithium ion concentration in the stored electrolyte of the electrolyte in at least one of the lithium ion secondary batteries,

wherein the charge and discharge control means comprises;

a plurality of mode control means for controlling charging and discharging each of the lithium ion secondary batteries on a predetermined charge and discharge condition, the mode control means including;

first mode control means for controlling charging and discharging each of the lithium ion secondary batteries on a first charge and discharge condition;

second mode control means for controlling charging and discharging each of the lithium ion secondary batteries on a second charge and discharge condition different from the first charge and discharge condition; and

third mode control means for controlling charging and discharging each of the lithium ion secondary batteries on a third charge and discharge condition different from the first and second charge and discharge conditions; and

mode selecting means for selecting one mode control means to be used from the plurality of mode control means,

wherein

when a comparison is made between a case of charging and discharging each of the lithium ion secondary batteries by the first mode control means, a case of charging and discharging each of the lithium ion secondary batteries by the second mode control means, and a case of charging and discharging each of the lithium ion secondary batteries by the third mode control means,

a discharge current by the second mode control means is made smaller on a predetermined discharge condition and also equal to or smaller on other discharge conditions than a discharge current by the first mode control means,

a charge current by the third mode control means is made smaller on a predetermined charge condition and also equal to or smaller on other charge conditions than a charge current by the first mode control means,

the mode selecting means is configured;

to select the second mode control means when the stored electrolyte concentration detecting means detects or estimates that the lithium ion concentration of the stored electrolyte is higher than a concentration threshold value for the second mode; and

to select the third mode control means when the stored electrolyte concentration detecting means detects or estimates that the lithium ion concentration of the stored electrolyte is lower than the concentration threshold value for the third mode lower than the concentration threshold value for the second mode.

11. The battery system according to claim 10, wherein

the predetermined discharge condition is a discharge condition where a maximum discharge current available by the first mode control means flows.

12. The battery system according to claim 10, wherein

the predetermined charge condition is a charge condition where a maximum charge current available by the first mode control means flows.

13. The battery system according to claim 10, wherein

on any one of the predetermined discharge condition and said other discharge conditions,

a discharge current by the second mode control means is made smaller than by the first mode control means.

14. The battery system according to claim 10, wherein

on any one of the predetermined charge condition and said other charge conditions,

a charge current by the third mode control means is made smaller than by the first mode control means.

15. The battery system according to claim 10, wherein

the stored electrolyte concentration detecting means comprises:

a first measuring electrode including;

a first electrode main part immersed in the stored electrolyte; and

a first conducting part exposed outside the battery case and electrically connected to the first electrode main part;

a reference electrolyte having a reference lithium ion concentration;

a reference electrolyte case part accommodating the reference electrolyte;

a second measuring electrode including;

a second electrode main part immersed in the reference electrolyte; and

a second conducting part exposed outside the reference electrolyte case part and electrically connected to the second electrode main part; and

a partition member having a first surface contacting the stored electrolyte and a second surface contacting the reference electrolyte for separating the stored electrolyte and the reference electrolyte from each other,

the partition member being configured to prevent ion movement between the first surface and the second surface resulting from a concentration difference between the stored electrolyte and the reference electrolyte, and to enable measurement of a potential between the reference electrolyte and the stored electrolyte by the first and second measuring electrodes.