# US 12,000,366 B2 · Vehicle electrical system and methods > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 12,000,366 B2 - Document ID: US12000366B2 - Status: Granted - Kind: B2 - Application number: 17/305,442 - Filed: 2021-07-07 - Published: 2021-10-28 - Granted: 2024-06-04 - Earliest claimed: 2019-01-07 - Assignees: Ford Global Technologies, LLC - Applicants: Ford Global Technologies, LLC - Inventors: Alexander O'Connor Gibson; David Lew - Web page: https://patentgrep.com/patent/US12000366B2 ## CPC - F02N 11/087: {Details of the switching means in starting circuits, e.g. relays or electronic switches} - B60R 16/0238: {Electrical distribution centers} - B60R 16/033: characterised by the use of electrical cells or batteries (for propulsion puposes B60K1/04; supplying batteries to, or removing batteries from, vehicles B60S5/06; testing of charge state G01R31/36) - F02N 11/006: {using a plurality of electric motors} - F02N 11/0866: {comprising several power sources, e.g. battery and capacitor or two batteries} - H02J 7/1423: {with multiple batteries} - H02J 7/342: {The other DC source being a battery actively interacting with the first one, i.e. battery to battery charging (with circuits for polarity protection H02J7/68)} - B60R 16/0315: {using multiplexing techniques (multiplexing for transmission of signals G08C15/00; multiplexing for electrical communication in general H04J)} - F02N 11/04: the motors being associated with current generators - F02N 2200/063: Battery voltage - F02N 2300/2002: using different starting modes, methods, or actuators depending on circumstances, e.g. engine temperature or component wear - H02J 2105/33: exchanging power with road vehicles - F02N: STARTING OF COMBUSTION ENGINES; STARTING AIDS FOR SUCH ENGINES, NOT OTHERWISE PROVIDED FOR - B60R: VEHICLES, VEHICLE FITTINGS, OR VEHICLE PARTS, NOT OTHERWISE PROVIDED FOR - H02J: ELECTRIC POWER NETWORKS; CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY ## Abstract Systems and methods for supplying electrical power between two electric energy storage devices are disclosed. In one example, an electric isolation switch is held open after engine starting until a voltage of a first electric energy storage device and a voltage of a second electric energy storage device are within a threshold voltage of at least one predetermined voltage level. ## Claims ### Claim 1 A power delivery method for a vehicle, comprising: reducing a voltage of a primary electric energy storage device via a controller after starting an engine via power supplied by the primary electric energy storage device and before closing an electric isolation switch that selectively couples the primary electric energy storage device to an accessory electric energy storage device. ### Claim 2 (depends on 1) The method of claim 1, further comprising opening the electric isolation switch via the controller before cranking an engine. ### Claim 3 (depends on 2) The method of claim 2, further comprising cranking the engine via an electric machine that is directly electrically coupled to the primary electric energy storage device, and where reducing the voltage is performed in response to a voltage of the primary electric energy storage device being greater than a voltage of the accessory electric energy storage device after starting the engine. ### Claim 4 (depends on 1) The method of claim 1, where the voltage of the primary electric energy storage device is reduced via a belt integrated starter/generator (BISG). ### Claim 5 (depends on 4) The method of claim 4, further comprising propelling a vehicle via a torque output from the BISG, the torque generated via electric power consumed reducing the voltage of the primary electric energy storage device. ### Claim 6 (depends on 1) The method of claim 1, further comprising decreasing an output voltage of a belt integrated starter/generator (BISG) before closing the electric isolation switch, the BISG electrically coupled to the primary electric energy storage device when the electric isolation switch is open. ### Claim 7 (depends on 1) The method of claim 1, further comprising closing the electric isolation switch in response to the voltage of the primary electric energy storage device being within a threshold voltage of a voltage of the accessory electric energy storage device. ### Claim 8 A power delivery method for a vehicle, comprising: increasing a voltage supplied to an accessory electric energy storage device via a DC/DC converter via a controller after starting an engine via power supplied by a primary electric energy storage device and before closing an electric isolation switch that selectively couples the primary electric energy storage device to the accessory electric energy storage device. ### Claim 9 (depends on 8) The method of claim 8, where the voltage supplied to the accessory electric energy storage device via the DC/DC converter is increased in response to a voltage of the accessory electric energy storage device being less than a threshold voltage when the electric isolation switch is open. ### Claim 10 (depends on 8) The method of claim 8, where the power is supplied to a belt integrated starter/generator, and further comprising: opening the electric isolation switch via the controller before cranking an engine. ### Claim 11 (depends on 8) The method of claim 8, further comprising cranking the engine via an electric machine that is directly electrically coupled to the primary electric energy storage device. ### Claim 12 (depends on 8) The method of claim 8, further comprising increasing a voltage supplied to the primary electric energy storage device via a belt integrated starter/generator after starting the engine and before closing the electric isolation switch. ### Claim 13 (depends on 8) The method of claim 8, where the voltage is increased in response to a voltage of the primary electric energy storage device being less than a threshold voltage. ### Claim 14 (depends on 8) The method of claim 8, where the DC/DC converter is electrically coupled to a third electric energy storage device the third electric energy storage device having a voltage that is more than double a voltage of the than the primary electric energy storage device. ### Claim 15 (depends on 14) The method of claim 14, where the DC/DC converter is electrically coupled to an inverter. ### Claim 16 (depends on 15) The method of claim 15, where the inverter is coupled to a belt integrated starter/generator. ### Claim 17 (depends on 8) The method of claim 8, further comprising determining a voltage of a first bus and a voltage of a second bus. ### Claim 18 (depends on 17) The method of claim 17, where the accessory electric energy storage device is coupled to the first bus and where the primary electric energy storage device is coupled to the second bus. ### Claim 19 (depends on 18) The method of claim 18, where increasing the voltage supplied to the accessory electric energy storage device is based on a voltage difference between the first bus and the second bus.