# US 4,394,611 A · Method for charging a storage battery > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 4,394,611 A - Document ID: US4394611A - Status: Granted - Kind: A - Application number: 06/198,341 - Filed: 1980-10-20 - Granted: 1983-07-19 - Earliest claimed: 1980-10-20 - Assignees: General Battery Corporation - Inventors: William H. Fallon; William R. Schober; Edward O. Neukirch; Donald W. Kirby - Web page: https://patentgrep.com/patent/US4394611A ## CPC - H02J 7/92: with prioritisation of loads or sources - H02J 7/96: in response to battery voltage - Y10S 320/17: Sensing of "gassing" voltage - H02J: ELECTRIC POWER NETWORKS; CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY - Y10S: TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS ## Abstract A method for charging a lead-acid storage battery, the method comprising the steps of charging the battery at an initially high rate during an initial stage of the charging cycle, monitoring the internal battery voltage, charging the battery at a lower, finishing rate after a preselected battery voltage has been monitored, and periodically interrupting the finishing charge until the battery is recharged. ## Claims ### Claim 1 A method for charging a storage battery, the method comprising: a. charging the battery at a first rate during a first portion of a charging cycle; b. charging the battery at a second rate, lower than the first rate, during a second portion of the charging cycle; and c. periodically interrupting the charging, at fixed, timed intervals, during the second portion of the charging cycle; d. wherein the interruption of the charging cycle defines a duty cycle wherein approximately one sixth of the charging cycle is interrupted during the second portion of the charging cycle. ### Claim 2 (depends on 1) The method of claim 1 wherein the second rate is approximately one third of the first rate. ### Claim 3 (depends on 2) The method of claim 2 wherein the second rate is initially approximately one third of the first rate, and thereafter tapers to approximately one tenth of the first rate. ### Claim 4 (depends on 1) The method of claim 1 wherein the duty cycle comprises approximately five minutes wherein the battery is charged at the second rate, and approximately one minute wherein the charging of the battery is interrupted. ### Claim 5 (depends on 1) The method of claim 1 further comprising switching the charging from the first rate to the second rate in response to the battery voltage. ### Claim 6 (depends on 5) The method of claim 5 wherein the charging rate is switched when the battery voltage attains a level lying within a range substantially between 2.30 and 2.37 volts per cell. ### Claim 7 (depends on 1) The method of claim 1 wherein the battery is charged at the first rate using a constant voltage, ferroresonant battery charger. ### Claim 8 (depends on 7) The method of claim 7 wherein the battery is charged at the second rate using a constant taper voltage charger. ### Claim 9 (depends on 1) The method of claim 1 wherein the battery is charged at the first and second rates using a single ferroresonant battery charger. ### Claim 10 A method for applying a finishing charge to a storage battery, the method comprising: a. charging the battery at a finishing rate during finishing portions of a charging cycle; and b. periodically interrupting the charging, at fixed, timed intervals, during the finishing portions of the charging cycle; c. wherein the interruption of the charging cycle defines a duty cycle wherein approximately one sixth of the charging cycle is interrupted during the finishing portions of the charging cycle. ### Claim 11 (depends on 10) The method of claim 10 wherein the finishing rate is a tapered rate. ### Claim 12 (depends on 11) The method of claim 11 wherein the finishing rate tapers downwardly to approximately one tenth of an initial charging rate preceeding the finishing charging. ### Claim 13 (depends on 10) The method of claim 10 wherein the duty cycle comprises approximately five minutes wherein the battery is charged at the finishing rate, and approximately one minute wherein the charging of the battery is interrupted. ### Claim 14 (depends on 10) The method of claim 10 further comprising automatically terminating the charging at the finishing rate after the battery has been fully charged. ### Claim 15 (depends on 14) The method of claim 14 wherein the termination is responsive to the battery voltage. ### Claim 16 (depends on 14) The method of claim 14 wherein the termination is responsive to a counted number of cycle interruptions. ### Claim 17 (depends on 14) The method of claim 14 wherein the termination is responsive to a selected overall time setting. ### Claim 18 (depends on 17) The method of claim 17 wherein the selected overall time setting commences after the battery has reached a selected voltage. ### Claim 19 (depends on 18) The method of claim 18 wherein the selected voltage is about 2.37 volts per cell. ### Claim 20 A method for charging a storage battery, the method comprising: a. charging the battery at a first rate during a first portion of a charging cycle; b. charging the battery at a second rate, which is approximately one third of the first rate, during a second portion of the charging cycle; and c. periodically interrupting the charging, at fixed, timed intervals, during the second portion of the charging cycle; d. wherein the timed interruption of the charging cycle defines a duty cycle wherein approximately one sixth of the charging cycle is interrupted during the second portion of the charging cycle. ### Claim 21 (depends on 1, 20) The method of claim 1 or 20 wherein the fixed, timed intervals are constant, timed intervals.