Rechargeable battery arrangement

• US 6,294,894 B1
• Filed: 08/09/2000
• Issued: 09/25/2001
• Est. Priority Date: 08/09/1999
• Status: Expired due to Term

• Current Assignee: Hitachi Maxell Limited (Hitachi, Ltd.)
• Original Assignee: Hitachi Maxell Limited (Hitachi, Ltd.)
• Inventors: Ochiai, Makoto, Suzuki, Masato
• Primary Examiner(s): Tso, Edward H.
• Application Number:
  US09/635,128
• Time in Patent Office: 412 Days
• Field of Search: 320/116, 320/127, 320/128, 320/132, 320/137, 320/149, 320/DIG.21, 324/426, 324/427, 324/433
• US Class Current: 320/132
• CPC Class Codes: G01R 31/396 Acquisition or processing of data for testing or for monitoring individual cells or groups of cells within a battery

Abstract

A rechargeable battery arrangement in which total service capacity for discharge from full charging to a final discharge voltage varies according to discharge conditions for discharging charged electric charge, comprising: an integration member which integrates quantity of electric charge discharged between a point of start of discharge after charging and the present; a data storage member for storing a plurality of total service capacities for discharge at a plurality of values of discharge current, respectively in unique association with a specific one of the total service capacities for discharge at a specific one of the values of discharge current; a current detection member for detecting a present value of discharge current; and a calculation member which obtains, from data obtained by the data storage member on the basis of the present value of discharge current detected by the current detection member, a total service capacity corresponding to or closest to the present value of discharge current and calculates, from the total service capacity and an integrated value obtained by the integration member, a residual capacity of electric charge for discharge.

Claims

1. A rechargeable battery arrangement in which total service capacity for discharge from full charging to a final discharge voltage varies according to discharge conditions for discharging charged electric charge, comprising:

an integration means which integrates quantity of electric charge discharged between a point of start of discharge after charging and the present;

a data storage means for storing a plurality of total service capacities for discharge at a plurality of values of discharge current, respectively in unique association with a specific one of the total service capacities for discharge at a specific one of the values of discharge current;

a current detection means for detecting a present value of discharge current; and

a calculation means which obtains, from data obtained by the data storage means on the basis of the present value of discharge current detected by the current detection means, a total service capacity corresponding to or closest to the present value of discharge current and calculates, from the total service capacity and an integrated value obtained by the integration means, a residual capacity of electric charge for discharge.

2. A rechargeable battery arrangement as claimed in claim 1, wherein the data storage means includes a table for associating the total service capacities with the values of discharge current and predetermined temperatures;

wherein the table employs the specific one of the total service capacities at a specific one of the predetermined temperatures as a reference total service capacity and stores the total service capacities as ratios of the total service capacities to the reference total service capacity.

3. A rechargeable battery arrangement as claimed in claim 2, which includes a plurality of battery cells connected to each other in series;

wherein the discharge current is electric current from the battery cells.

4. A rechargeable battery arrangement in which total service capacity for discharge from full charging to a final discharge voltage varies according to discharge conditions for discharging charged electric charge, comprising:

at least one battery cell;

a first data storage means for storing a plurality of total service capacities for discharge at a plurality of values of discharge current, respectively in unique association with a specific one of the total service capacities for discharge at a specific one of the values of discharge current;

a second data storage means for storing a plurality of integrated quantities of discharged electricity for discharge from full charging to a predetermined discharge voltage at the values of discharge current, respectively;

a voltage detection means for detecting a present voltage of the battery cell;

a current detection means for detecting a present value of discharge current;

a judgement means for judging whether or not the present voltage obtained by the voltage detection means is substantially coincident with the predetermined discharge voltage of the second data storage means; and

a calculation means which obtains, from data obtained by the first data storage means on the basis of the present value of discharge current detected by the current detection means, a total service capacity corresponding to or closest to the present value of discharge current in case the judgement means judges that the present voltage is substantially coincident with the predetermined discharge voltage;

wherein the calculation means obtains from the second data storage means one of the integrated quantities of discharged electricity corresponding to the present value of discharge current so as to calculate, from the total service capacity and the one of the integrated quantities of discharged electricity, a residual capacity of electric charge for discharge.

5. A rechargeable battery arrangement as claimed in claim 4, wherein a plurality of the battery cells are connected to each other in series.

6. A rechargeable battery arrangement as claimed in claim 4, wherein the first data storage means includes a table for associating the total service capacities with the values of discharge current and predetermined temperatures;

wherein the table employs the specific one of the total service capacities at a specific one of the predetermined temperatures as a reference total service capacity and stores the total service capacities as ratios of the total service capacities to the reference total service capacity.

7. A rechargeable battery arrangement as claimed in claim 5, wherein the first data storage means includes a table for associating the total service capacities with the values of discharge current and predetermined temperatures;

wherein the table employs the specific one of the total service capacities at a specific one of the predetermined temperatures as a reference total service capacity and stores the total service capacities as ratios of the total service capacities to the reference total service capacity.