# US 2018/0026464 A1 · Method of charging lithium metal battery > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2018/0026464 A1 - Document ID: US20180026464A1 - Status: Published application - Kind: A1 - Application number: 15/389,774 - Filed: 2016-12-23 - Published: 2018-01-25 - Earliest claimed: 2016-07-21 - Assignees: Samsung Electronics Co., Ltd.; Samsung SDI Co., Ltd. - Applicants: Samsung Electronics Co., Ltd.; Samsung SDI Co., Ltd. - Inventors: Wonseok CHANG; Myunghoon KIM; Hyorang KANG; Toshinori SUGIMOTO; Taehwan YU; Yonggun LEE; Hongsoo CHOI - Web page: https://patentgrep.com/patent/US20180026464A1 ## CPC - H01M 10/052: Li-accumulators - H01M 10/44: Methods for charging or discharging (circuits for charging H02J7/00) - H02J 7/00: Circuit arrangements for charging or discharging batteries or for supplying loads from batteries - H02J 7/90: Regulation of charging or discharging current or voltage - H02J 7/04: Regulation of charging current or voltage - H02J 7/92: with prioritisation of loads or sources - Y02E 60/10: Energy storage using batteries - H01M: PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY - H02J: ELECTRIC POWER NETWORKS; CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY - Y02E: REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION ## Abstract A method of charging a lithium metal battery includes charging the lithium metal battery so that a constant voltage period and a first constant current period are separated from each other in time where, the lithium metal battery is charged so that a second constant current period occurs between the first constant current period and the constant voltage period, and a current value of the second constant current period is less than a current value of the first constant current period. ## Claims ### Claim 1 A method of charging a lithium metal battery, the method comprising: charging the lithium metal battery so that a constant voltage period and a first constant current period are separated from each other in time. ### Claim 2 (depends on 1) The method of claim 1, wherein the lithium metal battery is charged so that a second constant current period occurs between the first constant current period and the constant voltage period, wherein a current value of the second constant current period is less than a current value of the first constant current period. ### Claim 3 (depends on 2) The method of claim 2, wherein the lithium metal battery is charged so that a third constant current period occurs between the second constant current period and the constant voltage period, and a current value of the third constant current period is less than that of the second constant current period. ### Claim 4 (depends on 2) The method of claim 2, wherein when a voltage of the constant voltage period is referred to as V1, the second constant current period occurs at a voltage equal to or greater than approximately 0.80V1. ### Claim 5 (depends on 3) The method of claim 3, wherein when a voltage of the constant voltage period is referred to as V1, the third constant current period occurs at a voltage equal to or greater than approximately 0.90V1. ### Claim 6 (depends on 2) The method of claim 2, wherein the current value of the second constant current period is equal to or less than approximately 80 percent of the current value of the first constant current period. ### Claim 7 (depends on 3) The method of claim 3, wherein the current value of the third constant current period is equal to or less than approximately 60 percent of the current value of the first constant current period. ### Claim 8 A method of charging a lithium metal battery, the method comprising: reducing a charge current to be lower than a current of a constant current period before a constant voltage period occurs. ### Claim 9 (depends on 8) The method of claim 8, wherein the reducing the charge current comprises discontinuously reducing the charge current until a point when the constant voltage period starts. ### Claim 10 (depends on 8) The method of claim 8, wherein the reducing the charge current comprises reducing the charge current at least once. ### Claim 11 (depends on 8) The method of claim 8, wherein the reducing the charge current comprises reducing the charge current at a voltage equal to or greater than approximately 80 percent of the voltage of the constant voltage period. ### Claim 12 A method of charging a lithium metal battery, in which a constant voltage period and a constant current period occur, the method comprising: confirming occurrence of a voltage drop before the constant voltage period occurs; measuring a degree of the voltage drop when the constant voltage period occurs; comparing the degree of the voltage drop with a set value; and reducing a charge current when the degree of the voltage drop is greater than the set value. ### Claim 13 (depends on 12) The method of claim 12, wherein when the degree of the voltage drop is less than the set value, the reducing the charge current comprises maintaining the charge current without reducing the charge current. ### Claim 14 (depends on 12) The method of claim 12, wherein when another voltage drop occurs after the charge current has been reduced, a subsequent process may be performed according to the processes which are performed after the voltage drop is occurred ### Claim 15 (depends on 12) The method of claim 12, wherein the reducing the charge current comprises reducing the charge current to be equal to or less than approximately 80 percent of a current value of the constant voltage period. ### Claim 16 (depends on 12) The method of claim 12, wherein the voltage drop occurs at a voltage equal to or greater than approximately 80 percent of the voltage of the constant voltage period. ### Claim 17 (depends on 14) The method of claim 14, wherein another voltage drop occurs at a voltage equal to or greater than approximately 90 percent of the voltage of the constant voltage period. ### Claim 18 (depends on 14) The method of claim 14, wherein when the reducing the charge current is repeated after the reducing the charge current, the charge current is reduced to be equal to or less than approximately 60 percent of a current value of the constant current period.