# US 12,770,942 B2 · System for charging a house battery bank from an alternator > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 12,770,942 B2 - Document ID: US12770942B2 - Status: Granted - Kind: B2 - Application number: 19/078,885 - Filed: 2025-03-13 - Published: 2026-01-29 - Granted: 2026-10-20 - Earliest claimed: 2024-07-26 - Assignees: Lithium Charging Concepts, Inc. - Applicants: Lithium Charging Concepts, Inc. - Inventors: Eric Johnson - Web page: https://patentgrep.com/patent/US12770942B2 ## CPC - H01M 10/441: {for several batteries or cells simultaneously or sequentially} - G01R 31/343: {in operation} - G01R 31/3835: involving only voltage measurements - H01M 2220/20: Batteries in motive systems, e.g. vehicle, ship, plane - H01M: PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY - G01R: MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES (indicating correct tuning of resonant circuits H03J3/12) ## Abstract In some embodiments, a system for charging a house battery bank in a vehicle is provided. The system comprises a disconnect solenoid electrically coupled to a starter battery and an alternator of the vehicle; and a controller monitor. The controller monitor is configured to adjust a disconnect signal to cause the disconnect solenoid to disconnect the starter battery from the alternator in response to detecting an ignition on signal and detecting a merge signal indicating an electrical connection between the house battery bank and at least one of the starter battery or the alternator. In some embodiments, a method of charging a house battery bank is provided that comprises charging at least one house battery bank with an alternator powered by an engine, and contemporaneously charging a starter battery with a direct current (DC) to DC charger powered by the alternator. ## Claims ### Claim 1 A system for charging a house battery bank in a vehicle, the system comprising: a starter battery junction; an alternator powered by an engine and configured to output power to the starter battery junction; a merge solenoid electrically coupled to the starter battery junction and the house battery bank; a DC to DC charger configured to receive power from the alternator via the starter battery junction; a disconnect solenoid electrically coupled to a starter battery and the starter battery junction; a voltage monitor electrically connected to the merge solenoid via a voltage sense wire; and a controller monitor; wherein the voltage monitor is configured to: in response to detecting a signal from an oil pressure switch and determining that a voltage sensed via the voltage sense wire is within a predetermined range, generate a merge signal to indicate an electrical connection between the house battery bank and at least one of the starter battery or the alternator, and transmit the generated merge signal to the controller monitor; and wherein the controller monitor is configured to: in response to detecting an ignition on signal and the merge signal generated by the voltage monitor: adjust a disconnect signal to cause the disconnect solenoid to disconnect the starter battery from the starter battery junction that is receiving power from the alternator; and adjust a remote On/Off signal generated by the controller monitor to turn the DC to DC charger on and thereby cause the DC to DC charger to provide power to the starter battery. ### Claim 2 (depends on 1) The system of claim 1, wherein the vehicle is a recreational vehicle (RV), a commercial motor vehicle (CMV), a boat, a yacht, an aircraft, a device having two or more battery banks of different chemistry, or a device having two or more battery banks having an incompatibility. ### Claim 3 (depends on 1) The system of claim 1, wherein the controller monitor is further configured to adjust the disconnect signal to cause the disconnect solenoid to reconnect the starter battery to the starter battery junction in response to at least one of the merge signal being removed or the ignition on signal being removed. ### Claim 4 (depends on 1) The system of claim 1, wherein the controller monitor further comprises: a time delay relay configured to receive the merge signal from the voltage monitor and configured to delay the adjustment of the disconnect signal and the remote On/Off signal. ### Claim 5 (depends on 1) The system of claim 1, further comprising a coupling solenoid electrically coupled to the starter battery and the DC to DC charger; wherein the controller monitor is further configured to: in response to detecting the merge signal generated by the voltage monitor: adjust a coupling signal to cause the coupling solenoid to connect the starter battery to the DC to DC charger. ### Claim 6 (depends on 5) The system of claim 5, wherein the controller monitor is further configured to: adjust the coupling signal to cause the coupling solenoid to disconnect the DC to DC charger from the starter battery in response to at least one of the merge signal being removed or the ignition on signal being removed. ### Claim 7 (depends on 1) The system of claim 1, wherein the controller monitor is further configured to: adjust the remote On/Off signal to turn the DC to DC charger off in response to the ignition on signal being removed. ### Claim 8 (depends on 5) The system of claim 5, wherein the controller monitor further comprises: at least one time delay relay configured to receive the merge signal from the voltage monitor and configured to delay the adjustment of at least one of the coupling signal or the remote On/Off signal. ### Claim 9 (depends on 1) The system of claim 1, wherein the voltage monitor is further configured to monitor a line voltage, an alternator voltage, a voltage of the ignition on signal, a voltage of the signal from the oil pressure switch, and a voltage between the alternator and the house battery bank. ### Claim 10 (depends on 9) The system of claim 9, wherein the voltage monitor is further configured to: stop generating and transmitting the merge signal to the controller monitor, thereby causing the controller monitor to adjust the disconnect signal to cause the disconnect solenoid to reconnect the starter battery to the starter battery junction and to adjust the remote On/Off signal to turn the DC to DC charger off in response to detecting at least one of the line voltage, the alternator voltage, the voltage of the ignition on signal, the voltage of the signal from the oil pressure switch, or the voltage between the alternator and the house battery bank is above or below an expected voltage range. ### Claim 11 (depends on 9) The system of claim 9, wherein monitoring the line voltage, the alternator voltage, the voltage of the ignition on signal, the voltage of the signal from the oil pressure switch, and the voltage between the alternator and the house battery bank comprises comparing each voltage to at least one of a first voltage threshold or a second voltage threshold. ### Claim 12 (depends on 10) The system of claim 10, wherein stopping the generating and transmitting the merge signal to the controller monitor further causes the controller monitor to: adjust the coupling signal to cause the coupling solenoid to disconnect the DC to DC charger from the starter battery. ### Claim 13 A method of charging a house battery bank, comprising: charging at least one house battery bank using power received via a closed merge solenoid that connects the house battery bank to a starter battery junction, wherein the starter battery junction receives the power from an alternator powered by an engine; and contemporaneously charging a starter battery that is disconnected from receiving power from the alternator via the starter battery junction by an open disconnect solenoid, wherein charging the starter battery includes charging the starter battery using power received from a DC to DC charger that receives power generated by the alternator via the starter battery junction. ### Claim 14 (depends on 13) The method of claim 13, further comprising: automatically disconnecting the starter battery from the alternator while the alternator is charging the at least one house battery bank. ### Claim 15 A method of charging at least one house battery bank, comprising: in response to detecting, by a voltage monitor, a signal from an oil pressure switch and determining that a voltage sensed from a merge solenoid via a voltage sense wire is within a predetermined range: generating, by the voltage monitor, a merge signal to indicate an electrical connection between the at least one house battery bank and at least one of a starter battery and an alternator; transmitting, by the voltage monitor, the merge signal to a controller monitor; and in response to detecting, by the controller monitor, an ignition on signal and the merge signal: disconnecting, by the controller monitor, the starter battery from a starter battery junction that is receiving power from the alternator. ### Claim 16 (depends on 15) The method of claim 15, wherein disconnecting the starter battery from the starter battery junction includes adjusting a disconnect signal to cause a disconnect solenoid to disconnect the starter battery from the starter battery junction. ### Claim 17 (depends on 15) The method of claim 15, further comprising: reconnecting the starter battery to the starter battery junction in response to the controller monitor detecting at least one of the ignition on signal being removed, the merge signal being removed, or power being disconnected. ### Claim 18 (depends on 17) The method of claim 17, wherein reconnecting the starter battery to the starter battery junction includes adjusting a disconnect signal to cause a disconnect solenoid to reconnect the starter battery to the starter battery junction. ### Claim 19 (depends on 15) The method of claim 15, further comprising: in response to detecting, by the controller monitor, the ignition on signal and the merge signal: performing, by the controller monitor, at least one of connecting the starter battery to a DC to DC charger or turning on the DC to DC charger. ### Claim 20 (depends on 19) The method of claim 19, wherein connecting the starter battery to the DC to DC charger includes adjusting a coupling signal to cause a coupling solenoid to connect the starter battery to the DC to DC charger. ### Claim 21 (depends on 19) The method of claim 19, further comprising: receiving, by the controller monitor, the merge signal from the voltage monitor via a time delay relay; and delaying, by the controller monitor, at least one of the connecting the starter battery to the DC to DC charger or the turning on the DC to DC charger using the time delay relay. ### Claim 22 (depends on 19) The method of claim 19, further comprising: performing at least one of disconnecting the starter battery from the DC to DC charger or turning off the DC to DC charger in response to detecting at least one of: the ignition on signal being removed, the merge signal being removed, power being disconnected, a line voltage being above a first voltage threshold or below a second voltage threshold, or an alternator voltage being above a first voltage threshold or below a second voltage threshold. ### Claim 23 (depends on 22) The method of claim 22, wherein disconnecting the starter battery from the DC to DC charger includes adjusting a coupling signal to cause a coupling solenoid to disconnect the starter battery from the DC to DC charger. ### Claim 24 (depends on 15) The method of claim 15, further comprising: reconnecting the starter battery to the starter battery junction in response to detecting at least one of: a line voltage is above or below an expected voltage range; an alternator voltage is above or below an expected voltage range; a loss of the ignition on signal; or a loss of the merge signal. ### Claim 25 (depends on 24) The method of claim 24, wherein reconnecting the starter battery to the starter battery junction includes adjusting a disconnect signal to cause a disconnect solenoid to connect the starter battery to the starter battery junction. ### Claim 26 (depends on 15) The method of claim 15, further comprising: receiving, by the controller monitor, the merge signal from the voltage monitor via a time delay relay; and delaying, by the controller monitor, the disconnecting of the starter battery from the starter battery junction using the time delay relay.