# US 2014/0197802 A1 · Electronic device > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2014/0197802 A1 - Document ID: US20140197802A1 - Status: Published application - Kind: A1 - Application number: 14/152,104 - Filed: 2014-01-10 - Published: 2014-07-17 - Earliest claimed: 2013-01-11 - Assignees: Semiconductor Energy Laboratory Co., Ltd. - Applicants: Semiconductor Energy Laboratory Co., Ltd. - Inventors: Shunpei YAMAZAKI - Web page: https://patentgrep.com/patent/US20140197802A1 ## CPC - H02J 7/00: Circuit arrangements for charging or discharging batteries or for supplying loads from batteries - H01M 10/0525: Rocking-chair batteries, i.e. batteries with lithium insertion or intercalation in both electrodes; Lithium-ion batteries - H01M 10/4235: {Safety or regulating additives or arrangements in electrodes, separators or electrolyte (H01M10/4242 takes precedence)} - H01M 10/44: Methods for charging or discharging (circuits for charging H02J7/00) - H02J 7/70: characterised by the mechanical construction - H02J 7/875: {Charging or discharging for charge maintenance, battery initiation or rejuvenation} - Y02E 60/10: Energy storage using batteries - H02J: ELECTRIC POWER NETWORKS; CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY - H01M: PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY - Y02E: REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION ## Abstract Degradation of a battery is prevented or the degree of the degradation is reduced, and charge and discharge performance of the battery is maximized and maintained for a long time. A reaction product, which is formed on an electrode surface and causes various malfunctions and degradation of a battery such as a lithium-ion secondary battery, is dissolved by application of electrical stimulus, specifically, by applying a signal to supply a current reverse to a current with which the reaction product is formed (reverse pulse current). ## Claims ### Claim 1 A method of charging an electronic device comprising: a first electrode; a second electrode; and an electrolytic solution between the first electrode and the second electrode, the method comprising: supplying a first current that flows between the first electrode and the second electrode in a first direction during a first period; and supplying a second current that flows between the first electrode and the second electrode in a second direction during a second period; wherein the first direction and the second direction are opposite to each other, wherein a reaction product grows on the first electrode by the supplying the first current, and wherein the reaction product on the first electrode is dissolved by supplying the second current. ### Claim 2 (depends on 1) The method of charging the electronic device according to claim 1, wherein the first period is longer than the second period. ### Claim 3 (depends on 1) The method of charging the electronic device according to claim 1, wherein supplying the second current is repeated after the reaction product is dissolved. ### Claim 4 (depends on 1) The method of charging the electronic device according to claim 1, wherein the first electrode is a negative electrode and the second electrode is a positive electrode. ### Claim 5 (depends on 1) The method of charging the electronic device according to claim 1, wherein the first electrode is a positive electrode and the second electrode is a negative electrode. ### Claim 6 (depends on 1) The method of charging the electronic device according to claim 1, wherein the electronic device is a battery that can be charged. ### Claim 7 (depends on 1) The method of charging the electronic device according to claim 1, the electronic device further comprising a protective film that covers part of the first electrode, wherein the reaction product that grows from a region of a surface of the first electrode that is not covered with the protective film is dissolved by supplying the second current. ### Claim 8 An electronic device comprising: a first electrode; a second electrode; and an electrolytic solution between the first electrode and the second electrode, wherein a reaction product that grows on the first electrode due to a first current that flows between the first electrode and the second electrode for a first period is dissolved by supplying a second current reverse to the first current for a second period. ### Claim 9 (depends on 8) The electronic device according to claim 8, wherein the first period is longer than the second period. ### Claim 10 (depends on 8) The electronic device according to claim 8, wherein supplying the second current is repeated after the reaction product is dissolved. ### Claim 11 (depends on 8) The electronic device according to claim 8, wherein the first electrode is a negative electrode and the second electrode is a positive electrode. ### Claim 12 (depends on 8) The electronic device according to claim 8, wherein the first electrode is a positive electrode and the second electrode is a negative electrode. ### Claim 13 (depends on 8) The electronic device according to claim 8, wherein the electronic device is a battery that can be charged. ### Claim 14 An electronic device comprising: a first electrode; a protective film that covers part of the first electrode; a second electrode; and an electrolytic solution between the first electrode and the second electrode, wherein a reaction product that grows from a region of a surface of the first electrode that is not covered with the protective film due to a first current that flows between the first electrode and the second electrode for a first period is dissolved by supplying a second current reverse to the first current for a second period. ### Claim 15 (depends on 14) The electronic device according to claim 14, wherein the first period is longer than the second period. ### Claim 16 (depends on 14) The electronic device according to claim 14, wherein supplying the second current is repeated after the reaction product is dissolved. ### Claim 17 (depends on 14) The electronic device according to claim 14, wherein the first electrode is a negative electrode and the second electrode is a positive electrode. ### Claim 18 (depends on 14) The electronic device according to claim 14, wherein the first electrode is a positive electrode and the second electrode is a negative electrode. ### Claim 19 (depends on 14) The electronic device according to claim 14, wherein the electronic device is a battery that can be charged.