Charge/discharge control method for rechargeable battery

• US 20010033150A1
• Filed: 05/15/2001
• Published: 10/25/2001
• Est. Priority Date: 11/24/1998
• Status: Active Grant

• Current Assignee: Matsushita Electric Industrial Company Limited (Panasonic Holdings Corporation), Toyota Jidosha Kabushiki Kaisha (Toyota Motor Corporation)
• Original Assignee: Matsushita Electric Industrial Company Limited (Panasonic Holdings Corporation)
• Inventors: Murakami, Yusai, Kimura, Tadao
• Granted Patent: US 6,573,687 B2
• Time in Patent Office: Days
• US Class Current: 320/132
• CPC Class Codes: H01M 10/345 Gastight metal hydride accumulators
• CPC Class Codes: H01M 10/44 Methods for charging or discharging circuits for charging H02J7/00
• CPC Class Codes: H01M 10/441 for several batteries or cells simultaneously or sequentially
• CPC Class Codes: H02J 7/0013 acting upon several batteries simultaneously or sequentially H02J7/1423 takes precedence
• CPC Class Codes: H02J 7/0014 Circuits for equalisation of charge between batteries
• CPC Class Codes: H02J 7/0071 with a programmable schedule
• CPC Class Codes: Y02B 40/00 Technologies aiming at improving the efficiency of home appliances, e.g. induction cooking or efficient technologies for refrigerators, freezers or dish washers
• CPC Class Codes: Y02E 60/10 Energy storage using batteries
• CPC Class Codes: Y02E 60/13 Energy storage using capacitors

Abstract

A battery pack is formed by serially connecting a plurality of cells, that are individually constructed as rechargeable batteries. Charging and discharging of this battery pack are controlled such that, the proportion of discharge current with respect to the charge current equals to a value obtained by multiplying the charge current by a charging efficiency corresponding to a target SOC value.

Claims

1. A method of controlling charge and discharge of a rechargeable battery constructed as part of a battery pack wherein a plurality of cells, individually constructed as rechargeable batteries, are connected in series, for equalizing the state of charge of each of the cells, characterized in that:

a charging efficiency of the rechargeable battery corresponding to a target value of SOC is obtained, and

the battery pack is charged and discharged repeatedly such that the proportion of a discharging amount relative to a charging amount is equal to the obtained charging efficiency.