US 12,392,840 B2
Method of predicting cycle life of secondary battery comprising carbon based hybrid negative electrode
Hyo-Jung Yoon, Daejeon (KR); So-Young Kim, Daejeon (KR); Ki-Won Sung, Daejeon (KR); and Eun-Ju Lee, Daejeon (KR)
Assigned to LG ENERGY SOLUTION, LTD., Seoul (KR)
Appl. No. 17/772,038
Filed by LG ENERGY SOLUTION, LTD., Seoul (KR)
PCT Filed Nov. 4, 2020, PCT No. PCT/KR2020/015352
§ 371(c)(1), (2) Date Apr. 26, 2022,
PCT Pub. No. WO2021/091236, PCT Pub. Date May 14, 2021.
Claims priority of application No. 10-2019-0139765 (KR), filed on Nov. 4, 2019.
Prior Publication US 2022/0373610 A1, Nov. 24, 2022
Int. Cl. G01R 31/392 (2019.01); H01M 10/42 (2006.01)
CPC G01R 31/392 (2019.01) [H01M 10/4285 (2013.01)] 11 Claims
OG exemplary drawing
 
1. A method of predicting cycle life of a secondary battery comprising a carbon-based hybrid negative electrode, the method comprising:
charging/discharging a target secondary battery comprising a carbon-based hybrid negative electrode including a carbon based negative electrode active material and a non-carbon based negative electrode active material in order to measure a lattice d-spacing of the carbon based negative electrode active material of the target carbon-based hybrid negative electrode using an X-ray diffractometer during the charging/discharging, and using the measurement to plot a graph of changes in a lattice d-spacing value as a function of charge/discharge capacity (X axis) of the target secondary battery;
calculating a target slope difference corresponding to a difference in slope value changed with respect to an inflection point of the graph during discharging in the plotted graph;
comparing the target slope difference with a reference slope difference corresponding to a difference in the slope value changed with respect to an inflection point in a graph showing changes in a lattice d-spacing value as a function of charge/discharge capacity (X axis) of a reference secondary battery;
predicting whether cycle life of the target secondary battery is improved compared to the reference secondary battery from a result of the comparison using the target slope difference of the target secondary battery being larger than the reference slope difference of the reference secondary battery, and determining that the target secondary battery in which a lower stress is applied to an artificial graphite has a longer cycle life than the reference secondary battery based on the target slope difference that is larger; and
using the target secondary battery as a power source based on the cycle life of the target secondary battery compared to the reference secondary battery when the target slope difference is larger than the reference slope difference from the result of the comparison to confirm a prediction from the predicting.