Charging Method of Battery Pack, Management Method of Storage System, Management Apparatus of Battery Pack, Storage System, and Non-Transitory Storage Medium

Patent metadata

Field	Value
Publication number	US-2024097476-A1
Application number	US-202318175616-A
Country	US
Kind code	A1
Filing date	Feb 28, 2023
Priority date	Sep 16, 2022
Publication date	Mar 21, 2024
Grant date	—

Abstract

In one embodiment, there is provided a charging method of a battery pack in which a plurality of aqueous battery cells are electrically connected in series. In this charging method, in a case where the battery pack reaches a reference voltage by a constant-current charging at a first charging rate, constant-current charging is performed on the battery pack at the second charging rate lower than the first charging rate and being from 0.01 C or more to 0.05 C or less. Then, this constant-current charging at the second charging rate is continued until a charged electric charge amount from a start timing of the constant-current charging at the second charging rate reaches a reference electric charge amount set from 1% or more to 5% or less of the nominal capacity of the battery pack.

First claim

What is claimed is:

1 . A charging method of a battery pack in which a plurality of aqueous battery cells each including an aqueous electrolyte, a positive electrode, and a negative electrode are electrically connected in series, comprising:
performing constant-current charging on the battery pack at a first charging rate until a voltage of the battery pack reaches a reference voltage; performing constant-current charging on the battery pack at a second charging rate that is lower than the first charging rate and is from 0.01 C or more to 0.05 C or less, in response to arrival of the battery pack at the reference voltage by the constant-current charging at the first charging rate; and continuing the constant-current charging at the second charging rate until a charged electric charge amount from a start timing of the constant-current charging at the second charging rate reaches a reference electric charge amount set from 1% or more to 5% or less of a nominal capacity of the battery pack.

2 . The method according to claim 1 , further comprising setting the reference voltage for the voltage of the battery pack based on a temperature of the battery pack.

3 . The method according to claim 2 , wherein in the setting of the reference voltage of the batter pack, the reference voltage is set to be lower as the temperature of the battery pack becomes higher.

4 . The method according to claim 1 , further comprising setting the reference voltage such that a value obtained by dividing the reference voltage by the number of serially connected aqueous battery cells in the battery pack is from 2.40 V or more to 2.75 V or less.

5 . A management method of a storage system including a plural of the battery pack, comprising performing a charging method according to claim 1 on each of the plurality of battery packs, based on a condition that a difference between a maximum voltage that is highest of voltages of the plurality of battery packs and a minimum voltage that is lowest of the voltages of the plurality of battery packs is larger than 5% of the maximum voltage.

6 . A management apparatus of a battery pack in which a plurality of aqueous battery cells each including an aqueous electrolyte, a positive electrode, and a negative electrode are electrically connected in series, comprising a control unit configured to:
perform constant-current charging on the battery pack at a first charging rate until a voltage of the battery pack reaches a reference voltage; perform constant-current charging on the battery pack at a second charging rate that is lower than the first charging rate and is from 0.01 C or more to 0.05 C or less, in response to arrival of the battery pack at the reference voltage by the constant-current charging at the first charging rate; and continue the constant-current charging at the second charging rate until a charged electric charge amount from a start timing of the constant-current charging at the second charging rate reaches a reference electric charge amount set from 1% or more to 5% or less of a nominal capacity of the battery pack.

7 . A storage system comprising:
a management apparatus according to claim 6 ; and the battery pack which includes the plurality of aqueous battery cells electrically connected in series, and charging of which is controlled by the control unit of the management apparatus.

8 . The system according to claim 7 , further comprising a battery-mounted apparatus in which the battery pack is mounted.

9 . The system according to claim 7 , wherein the battery pack includes a plural of the battery pack, and
based on a condition that a difference between a maximum voltage that is highest of voltages of the plurality of battery packs and a minimum voltage that is lowest of the voltages of the plurality of battery packs is larger than 5% of the maximum voltage, the control unit of the management apparatus sequentially performs, on each of the plurality of battery packs, the constant-current charging at the first charging rate until the reference voltage is reached, and the constant-current charging at the second charging rate until the reference electric charge amount is reached after the reference voltage is reached.

10 . A non-transitory storage medium storing a charging program of a battery pack in which a plurality of aqueous battery cells each including an aqueous electrolyte, a positive electrode, and a negative electrode are electrically connected in series, wherein the charging program causes a computer to:
perform constant-current charging on the battery pack at a first charging rate until a voltage of the battery pack reaches a reference voltage; perform constant-current charging on the battery pack at a second charging rate that is lower than the first charging rate and is from 0.01 C or more to 0.05 C or less, in response to arrival of the battery pack at the reference voltage by the constant-current charging at the first charging rate; and continue the constant-current charging at the second charging rate until a charged electric charge amount from a start timing of the constant-current charging at the second charging rate reaches a reference electric charge amount set from 1% or more to 5% or less of a nominal capacity of the battery pack.

Assignees

• Toshiba Kk

Inventors

• Hoshina Keigo
• Seki Hayato
• Matsuno Shinsuke
• Takami Norio

Classifications

• H02J7/80

  including monitoring or indicating arrangements · CPC title

• H02J7/52

  for charge balancing, e.g. equalisation of charge between batteries · CPC title

• H02J7/96 Primary

  in response to battery voltage · CPC title

• H02J2105/37

  exchanging power with electric vehicles [EV] or with hybrid electric vehicles [HEV] · CPC title

• H02J7/007182 Primary

  Electricity · mapped topic