BATTERY PACK MANUFACTURING METHOD, AND BATTERY PACK

• US 20100047684A1
• Filed: 05/09/2008
• Published: 02/25/2010
• Est. Priority Date: 05/22/2007
• Status: Active Grant

• Current Assignee: Panasonic EV Energy Company, Limited (Toyota Motor Corporation)
• Original Assignee: Panasonic EV Energy Company, Limited (Toyota Motor Corporation)
• Inventors: Okumura, Motoyoshi, Maegawa, Katsunori
• Granted Patent: US 8,470,470 B2
• Time in Patent Office: Days
• US Class Current: 429/156
• CPC Class Codes: H01M 10/42 Methods or arrangements for servicing or maintenance of secondary cells or secondary half-cells H01M10/60 takes precedence
• CPC Class Codes: H01M 10/4207 for several batteries or cells simultaneously or sequentially
• CPC Class Codes: H01M 10/48 Accumulators combined with arrangements for measuring, testing or indicating the condition of cells, e.g. the level or density of the electrolyte constructional details of current conducting connections for detecting conditions inside cells or batteries, e.g. details of voltage sensing terminals, H01M50/569
• CPC Class Codes: H01M 50/209 adapted for prismatic or rectangular cells H01M50/216 takes precedence
• CPC Class Codes: Y02E 60/10 Energy storage using batteries
• CPC Class Codes: Y10T 29/49108 Electric battery cell making

Abstract

Provided are a battery pack manufacturing method, which can prevent a drawback that some of used secondary batteries constituting a battery pack prematurely come to the end and which can suppress the enlargement of the temporary voltage difference between the used secondary battery at a charging/discharging time (especially in a low-temperature circumstance), and a battery pack. The battery pack manufacturing method comprises an acquiring step (Step S1) of acquiring the individual internal resistances of the secondary batteries already used, a selection step (Step S2) of selecting a plurality of the used secondary batteries having the internal resistances close to each other from a group of the used secondary batteries whose internal resistances have been acquired, and an assembling step (Step S3) of combining the used secondary batteries selected, to constitute the battery pack.

Claims

1. A method of manufacturing a battery pack comprising in combination a plurality of used secondary batteries, comprising the steps of:

acquiring an internal resistance value of each of the used secondary batteries having ever been used;

selecting a plurality of the used secondary batteries whose internal resistance values are close to each other from a group of the used secondary batteries whose internal resistance values have been acquired; and

assembling the selected used secondary batteries to constitute the battery pack.

2. The method of manufacturing the battery pack according to claim 1, wherein

the step of selecting a plurality of the used secondary batteries includes selecting the used secondary batteries so that a difference in internal resistance value between the used secondary battery having a maximum internal resistance value and the used secondary battery having a minimum internal resistance value among the selected used secondary batteries is 20% or less of the internal resistance value of the used secondary battery having the minimum internal resistance value.

3. A battery pack comprising in combination a plurality of used secondary batteries having ever been used, wherein

a difference in internal resistance value between the used secondary battery having a maximum internal resistance value and the used secondary battery having a minimum internal resistance value among the selected used secondary batteries is 20% or less of the internal resistance value of the used secondary battery having the minimum internal resistance value.