Method for reusing vehicle rechargeable battery

• US 10,355,325 B2
• Filed: 02/11/2016
• Issued: 07/16/2019
• Est. Priority Date: 02/17/2015
• Status: Active Grant

• Current Assignee: Primearth EV Energy Company Limited (Toyota Motor Corporation), Toyota Jidosha Kabushiki Kaisha (Toyota Motor Corporation)
• Original Assignee: Primearth EV Energy Company Limited (Toyota Motor Corporation)
• Inventors: Koba, Daisuke, Ito, Shinichiro, Nakagiri, Yasushi, Fukuma, Tamotsu, Ichikawa, Kouichi, Takahashi, Yasuhiro, Mitsui, Masahiko
• Primary Examiner(s): Arbes, Carl J
• Application Number:
  US15/041,882
• Publication Number:
  US 20160240898A1
• Time in Patent Office: 1,251 Days
• CPC Class Codes: B60L 50/64 Constructional details of batteries specially adapted for electric vehicles
• CPC Class Codes: G01R 31/3842 combining voltage and current measurements
• CPC Class Codes: G01R 31/389 Measuring internal impedance, internal conductance or related variables
• CPC Class Codes: H01M 10/44 Methods for charging or discharging circuits for charging H02J7/00
• CPC Class Codes: H01M 10/54 Reclaiming serviceable parts of waste accumulators
• CPC Class Codes: H01M 2220/20 Batteries in motive systems, e.g. vehicle, ship, plane
• CPC Class Codes: Y02E 60/10 Energy storage using batteries
• CPC Class Codes: Y02T 10/70 Energy storage systems for electromobility, e.g. batteries
• CPC Class Codes: Y02W 30/84 Recycling of batteries or fuel cells

Abstract

A method for reusing a vehicle rechargeable battery to rebuild an assembled battery from a plurality of battery units having a usage history is provided. The method includes measuring a remaining charge of each of a plurality of battery units obtained by dismantling an assembled battery having a usage history. The method further includes selecting from the battery units a battery unit in which the measured remaining charge is greater than or equal to a remaining charge lower limit value, which is set in a range that is greater than zero and less than a lower limit value of a remaining charge control range of a vehicle in which the assembled battery was installed, and assembling a new assembled battery using the selected battery unit.

Claims

1. A method for reusing a vehicle rechargeable battery to rebuild an assembled battery from a plurality of battery units having a usage history, the method comprising:

measuring a remaining charge of each of a plurality of battery units obtained by dismantling an assembled battery having a usage history associated with a vehicle in which the assembled battery was installed, the usage history including a remaining charge control range of the vehicle, the remaining charge control range including a lower limit value;

measuring an internal resistance of each of the plurality of battery units;

selecting from the plurality of battery units a battery unit in which;

the measured remaining charge is greater than or equal to a remaining charge threshold value L_m, wherein the remaining charge threshold value L_m is greater than zero and less than the lower limit value of the remaining charge control range; and

the measured internal resistance is in a predetermined range; and

assembling a new assembled battery using the selected battery unit.

2. The method according to claim 1, wherein the remaining charge threshold value L_m is less than or equal to 80% of the lower limit value of the remaining charge control range.

3. The method according to claim 1, further comprising selecting from the plurality of battery units a battery unit in which a capacity balance is normal between a positive electrode and a negative electrode.

4. The method according to claim 3, wherein

the selecting from the plurality of battery units a battery unit in which a capacity balance is normal includes

measuring a first complex impedance of the battery unit at a first frequency in a diffusion region,

measuring a second complex impedance of the battery unit at a second frequency in the diffusion region,

calculating an inclination angle of a straight line or an approximation straight line that connects on a graph the first and second complex impedances of the battery unit corresponding to the first and second frequencies in the diffusion region, and

determining whether or not the capacity balance is normal by comparing the inclination angle with a threshold value.

5. The method according to claim 1, further comprising, after selecting the battery unit in which the measured remaining charge is greater than or equal to the remaining charge threshold value L_m, charging the battery unit to a predetermined charge amount or greater.

6. The method according to claim 1, further comprising charging the selected battery unit or the new assembled battery including the selected battery unit.

7. The method according to claim 1, wherein

the remaining charge control range of the assembled battery is specified by a charge ratio that indicates a ratio of a charge amount relative to a charge capacity of the assembled battery, and

the lower limit value of the remaining charge control range is set to be greater than or equal to 40% in the charge ratio.

8. The method according to claim 1, further comprising measuring at least one of open end voltage and batter massy for each battery unit, wherein the selecting further comprises selecting from the plurality of battery units a battery unit in which at least one of:

the measured open end voltage is in an open end voltage tolerable range;

or

the measured battery mass is in a battery mass tolerable range.