Power supply system and state of charge estimating method

• US 6,366,055 B1
• Filed: 03/26/2001
• Issued: 04/02/2002
• Est. Priority Date: 03/30/2000
• Status: Expired due to Term

• Current Assignee: Shin-Kobe Electric Machinery Company Limited (Resonac Holdings Corp.)
• Original Assignee: Shin-Kobe Electric Machinery Company Limited (Resonac Holdings Corp.)
• Inventors: Morimoto, Yoshinari, Yamada, Keizo, Shimoura, Ichiro, Maeda, Kenichi, Hirasawa, Tokiyoshi, Minoura, Satoshi, Ookoshi, Tetsuro, Okuda, Yoshihisa
• Primary Examiner(s): TOATLEY, GREGORY J
• Application Number:
  US09/816,145
• Time in Patent Office: 372 Days
• Field of Search: 320/103, 320/126, 320/134, 320/132, 320/106, 429/61, 307/150, 307/48
• US Class Current: 320/134
• CPC Class Codes: B60R 16/03 for supply of electrical power to vehicle subsystems or for circuit arrangements for charging batteries H02J7/00
• CPC Class Codes: H02J 2310/46 for ICE-powered road vehicles
• CPC Class Codes: H02J 7/1423 with multiple batteries
• CPC Class Codes: Y02P 70/50 Manufacturing or production processes characterised by the final manufactured product

Abstract

A power system where energy generated at a deceleration time of a running vehicle such as an automobile can be accepted as regenerative energy sufficiently and safely is provided. In a power system 10, a non-aqueous solution system secondary battery group 1 where 10 to 11 lithium ion secondary battery cells are connected in series and an aqueous solution system secondary battery group 2 where 18 control valve type lead-acid battery cells are connected in series are connected in parallel. The battery capacity of the non-aqueous solution system secondary battery group 1 is smaller than that of the aqueous solution system secondary battery group 2. The non-aqueous solution system secondary battery group 1 and the aqueous solution system secondary battery group 2 are charged at a current value of 7C or less from a motor generator 3, and the ratio of the charged current value of the aqueous solution system secondary battery group 2 to the charged current value of the non-aqueous solution system secondary battery group 1 is 0.05 to 1.00.

Claims

1. A 42V power system which is mounted on a vehicle and which can receive electrical power supplied from a generator, comprising:

an aqueous solution system secondary battery group where a plurality of aqueous solution system cells are connected; and

a non-aqueous solution system secondary battery group which is connected to the aqueous solution system secondary battery group in parallel, which has a group battery capacity smaller than that of the aqueous solution system secondary battery group, and where a plurality of non-aqueous solution system cells are connected.

2. A 42V power system according to claim 1, wherein a ratio (X/Y) of a value (X) of current flowing through the aqueous solution system secondary battery group and a value (Y) of current flowing through the non-aqueous solution system secondary battery group is set to 0.05 or more and 1.00 or less during charging at a current value where charging rate is 7 C or less.

3. A 42V power system according to claim 1, wherein regeneration acceptance ability (A/l·

kg) of the non-aqueous solution system secondary battery group is larger than that of the aqueous solution system secondary battery group.

4. A 42V power system according to claim 1, wherein a value of current charging the non-aqueous solution system secondary battery group is larger than that of current charging the aqueous solution system secondary battery group.

5. A 42V power system according to claim 1, wherein charging voltage of the non-aqueous solution system secondary battery group is set to 4.2V/cell or less.

6. A 42V power system according to claim 1, further comprising a battery controller which controls at least a state of charge of the non-aqueous solution system secondary battery group.

7. A 42V power system according to claim 6, wherein the battery controller controls a state of charge of the aqueous solution system secondary battery group on the basis of the state of charge of the non-aqueous solution system secondary battery group.

8. A 42V power system according to claim 7, wherein the battery controller controls the state of charge of the aqueous solution system secondary battery group on the basis of a relationship between the state of charge and a battery voltage of the non-aqueous solution system secondary battery group.

9. A 42V power system according to claim 6, wherein the battery controller controls respective states of charge of the aqueous solution system secondary battery group and the non-aqueous solution system secondary battery group independently.

10. A 42V power system according to claim 1, wherein a charging path for charging the non-aqueous solution system secondary battery group is different from a charging path for charging the aqueous solution system secondary battery group.

11. A 42V power system according to claim 10, further comprising a flow divider which divides current so as to maintain the states of charge of the aqueous solution system secondary battery group and the non-aqueous solution system secondary battery group in the same level, wherein a charging/discharging circuit of the aqueous solution system secondary battery group and a charging/discharging circuit of the non-aqueous solution system secondary battery group are connected to each other through the flow divider.

12. A 42V power system according to claim 11, wherein the flow divider divides current on the basis of a group battery capacity ratio of the aqueous solution system secondary battery group and the non-aqueous solution system secondary battery group.

13. A 42V power system according to claim 6, further comprising a DC/DC converter which causes the voltage of the non-aqueous solution system secondary battery group to coincide with the battery voltage of the aqueous solution system secondary battery group.

14. A 42V power system according to claim 1, wherein one of the aqueous solution system secondary battery group and the non-aqueous solution system secondary battery group has a discharging path reaching a vehicle starter.

15. A 42V power system according to claim 1, wherein the aqueous solution system cell is a lead-acid battery.

16. A 42V power system according to claim 15, wherein the lead-acid battery is a 36V system control valve type lead-acid battery.

17. A 42V power system according to claim 1, wherein the non-aqueous solution system cell is a lithium secondary battery.

18. A 42V power system according to claim 17, wherein the lithium secondary battery is a 36V system lithium ion secondary battery.

19. A 42V power system according to claim 1, wherein the aqueous solution system secondary battery group is structured by 18 lead-acid batteries connected in series, and the non-aqueous solution system secondary battery group is structured by 10 to 11 lithium secondary batteries connected in series.

20. A 42V power system according to claim 1, wherein the aqueous solution system secondary battery group and the non-aqueous solution system secondary battery group are accommodated in a mono-block container having 20 cell chambers partitioned in an array of two rows and ten columns;

the non-aqueous solution system cells of the non-aqueous solution system secondary battery group connected by the number of 18 in series are accommodated in a cell chamber of the first row and the first column and/or a cell chamber of the first row and the tenth column of the mono-block container;

the aqueous solution system cells of the aqueous solution system secondary battery group are accommodated in 18 cell chambers of respective cell chambers defined at the first row and the second to ninth columns and respective cell chambers defined at the second row and all the columns of the mono-block container;

the 18 aqueous solution system cells are connected in series by connecting members for connecting adjacent cell chambers in the order of the second row and the first column, the second row and the second column, the first row and the second column, the first row and the third column, the second row and the third column, the second row and the fourth column, the first row and the fourth column, the first row and the fifth column, the second row and the fifth column, the second row and the sixth column, the first row and the sixth column, the first row and the seventh column, the second row and the seventh column, the second row and the eighth column, the first row and the eighth column, the first row and the ninth column, the second row and the ninth column, and the second row and the tenth column; and

the cell chamber defined at the second row and the first column and the cell chamber defined at the second row and the tenth column are provided with external output terminals.

21. A state of charge estimating method for estimating a state of charge of the 42V power system according to claim 11, wherein the state of charge of the aqueous solution system secondary battery group is estimated by detecting the state of charge of the non-aqueous solution system secondary battery group.

22. A state of charge estimating method according to claim 21, wherein the state of charge of the aqueous solution system secondary battery group is estimated by detecting respective initial states of charge of the aqueous solution system secondary battery group and the non-aqueous solution system secondary battery group and the change rate of the state of charge of the non-aqueous solution system secondary