US 12,292,401 B2
Weld portion inspection method using thermal image sensing
Mun Chae Joung, Daejeon (KR); and Hang June Choi, Daejeon (KR)
Assigned to LG ENERGY SOLUTION, LTD., Seoul (KR)
Appl. No. 17/619,975
Filed by LG ENERGY SOLUTION, LTD., Seoul (KR)
PCT Filed Oct. 21, 2020, PCT No. PCT/KR2020/014365
§ 371(c)(1), (2) Date Dec. 16, 2021,
PCT Pub. No. WO2021/107407, PCT Pub. Date Jun. 3, 2021.
Claims priority of application No. 10-2019-0153866 (KR), filed on Nov. 27, 2019.
Prior Publication US 2022/0357294 A1, Nov. 10, 2022
Int. Cl. G01N 25/72 (2006.01); B23K 31/12 (2006.01); H01M 10/48 (2006.01)
CPC G01N 25/72 (2013.01) [B23K 31/125 (2013.01); H01M 10/486 (2013.01)] 10 Claims
OG exemplary drawing
 
1. A method of inspecting a weld portion between a lead portion of a battery cell and a busbar, the method comprising:
a first operation of welding lead portions of two or more battery cells including the battery cell and the busbar to form weld portions that include the weld portion;
a second operation of turning on a switch connected to the two or more battery cells such that the two or more battery cells are electrically connected to each other;
a third operation of heating the weld portion using Joule heat and continuously measuring a change in temperature over time of the weld portion; and
a fourth operation of determining whether the weld portion is defective based on a temperature increase pattern of the weld portion obtained from the continuously measuring of the change in the temperature over time,
wherein the second operation is maintained for a predetermined time after the two or more battery cells are discharged, and
wherein the third operation is performed until the two or more battery cells are completely discharged.