Voltage and Current Monitoring Systems for EV Batteries

Method to determine the performance of electric vehicle batteries without accessing the internal vehicle electronics. The method involves using an external charging device that can be detached from the vehicle. Current and voltage are measured outside the vehicle while applying a variable current increase or decrease to the battery. This allows determining the battery's resistance and performance without influencences from vehicle components. Environmental conditions like temperature are also factored in to compensate for parasitic effects.

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Determining short circuit risk in battery cells after manufacturing to reduce fire hazards. The technique involves monitoring self-discharge current and voltage during cell standby periods to calculate a total resistance. If the calculated resistance is below a threshold, it indicates accelerated short circuit degradation and raises a short circuit risk alert.

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Isolation resistance monitoring for battery management systems (BMS) in electric vehicles (EVs) that enables accurate and cost-effective isolation resistance measurement for both the high-voltage (HV) battery pack and the floating high-voltage link side when disconnected. The monitoring uses a single device and power supply powered from the 12V auxiliary voltage of the EV. The device applies a test voltage from the auxiliary supply to a resistor, measures the resulting current, and calculates the isolation resistance. This allows isolation resistance monitoring for both the HV pack and link sides using just one device and power source, simplifying and reducing cost compared to separate monitoring for each side.

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A power module for electric vehicles with integrated current sensing capability. The module has semiconductor chips mounted on a substrate and a lead with an extended portion connected to the substrate and protruding outward. The lead has a resistance portion between the substrate end and the protruding end. This integrated lead structure serves as a current sensor without requiring a separate external sensor or internal resistors. The extended lead protrusion provides access to measure current flowing through the module.

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Battery cell management chip for individual battery cells in a battery pack that enables real-time monitoring and protection of each cell to improve battery life and performance. The chip acquires parameters like voltage, temperature, and stress from the cell, compares them to dynamic thresholds, and adjusts cell operation if needed. It also wirelessly communicates with the pack controller to coordinate cell balancing and protection. The chip reduces cell failure risks compared to pack-level monitoring by detecting faults early and preventing cascading failures.

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Detecting thermal events in parallel-connected battery cells of an electric vehicle battery pack using voltage rebound monitoring. The technique involves confirming a voltage rebound in a group of parallel-connected cells as a faster and more effective way to detect thermal events compared to just monitoring voltage drop below a threshold. The voltage rebound is a characteristic voltage behavior during thermal propagation in parallel cells where the voltage rebounds slightly after an initial drop. Detecting this rebound along with other conditions like high temperature or pressure confirms a thermal event.

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Predicting and preventing thermal runaway in battery packs used in vehicles to prevent cascading cell failures. The method involves monitoring cell parameters like voltage, current, and temperature during charging to determine the charging response. This response is then analyzed to estimate the likelihood of thermal runaway. The vehicle operation can then be controlled to prevent runaway based on this predicted risk.

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Battery monitoring system for electric vehicles that detects potential cell imbalances and thermal runaway risks by ranking cell voltages and analyzing the ranking differences over time. The system uses a sensor to get cell voltages, sorts them into a ranking, repeats the ranking at regular intervals, and compares the changes. If a cell's ranking consistently lags behind, it indicates potential imbalance. If adjacent cells' rankings increase while the lagging cell's stays low, it indicates thermal runaway risk. The system uses this analysis to control battery operation and predict thermal runaway.

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Battery management system that can detect battery degradation and abnormal behavior more accurately than existing methods. The system estimates future battery voltage based on current and initial voltage during a period, then compares it to actual voltage during the next period. If the difference exceeds a threshold, it indicates abnormality. The system learns a relationship between current and voltage using an algorithm, then updates it periodically. This allows estimating voltage for replaced batteries using the stored algorithm.

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Early warning system to detect thermal runaway risk in electric vehicles before it becomes critical. The system monitors cell voltages over time to identify voltage characteristics indicative of thermal runaway. It divides the cell voltage data into time windows based on collection timing, extracts voltage characteristics from each window, and checks if they meet thresholds to determine if the vehicle has a runaway risk. If so, it alerts the user to replace the battery before runaway occurs.

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New energy vehicle charging safety monitoring system that uses Zigbee communication for real-time monitoring of battery data during charging. The system has a charging module, communication module, processor, cloud storage, real-time monitoring, and alarm modules. It collects battery voltage, temperature, and current during charging and sends the data to the cloud for storage and analysis. The real-time monitoring module displays battery status and estimates SOH. Historical data comparison helps identify battery issues. The alarm module alerts on abnormal data. This allows proactive detection and resolution of charging-related battery problems.

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Online monitoring method for vehicle lithium batteries to improve safety and longevity by continuously tracking battery parameters like voltage, current, and temperature to accurately estimate battery power and remaining capacity. The monitoring allows proactive management of charging, discharging, and temperature to optimize battery performance and prevent issues like overcharging, overdischarging, or overheating.

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Smart battery monitoring system to improve battery reliability, performance, and lifespan. The system uses a central controller connected to a battery pack monitoring host and a battery management system host. The battery pack host has modules to measure voltage, temperature, internal resistance, and SOC/SOH of individual batteries. The battery management host monitors pack voltage, current, and temperature. The controller, monitoring center, and cloud server provide real-time monitoring, protection, and early warning against issues like thermal runaway, open circuits, overvoltage, etc. The system enables comprehensive battery performance analysis, balancing, and optimization to extend battery life.

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Real-time monitoring and control of individual rechargeable battery cells in a battery bank to detect and prevent faults, optimize performance, and extend life. The method involves measuring voltage, current, and temperature of each cell using onboard sensors, and sending the data to a central unit. The unit calculates cell state, health, charge/discharge times, and replacement time. It stores the data and compares against ranges. If outside, it initiates preventive/corrective actions like regulating energy flow or alerting. This allows precise real-time monitoring and control of each cell to anticipate and address issues before they spread to the bank.

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Detecting and mitigating thermal runaway in vehicle battery packs to prevent cell fires. The method involves monitoring cell voltage and temperature in a vehicle battery pack. If a cell short occurs, it analyzes the voltage signal using techniques like wavelet transforms and power spectra to detect rapid voltage modulations and energy releases indicating thermal runaway. If runaway is confirmed, it initiates actions like stopping charging, releasing pressure, cooling, warning, and contacting emergency services.

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Detecting thermal runaway of battery cells in electric vehicles to quickly alert occupants of potential fire hazards. The system uses multiple sensing lines to monitor battery voltages. Main lines connect to individual cells to measure their voltages. Auxiliary lines connect to input and output terminals of the battery module. By comparing the sum of cell voltages to the module voltage, abnormalities in cells or main lines can be detected. If the cell sum and module voltages match, all is normal. If they differ, further checks are made. If module voltage is normal, the main lines are faulty. If module voltage is abnormal, the cells have runaway. This rapid detection allows warning occupants before serious damage occurs.

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Real-time monitoring system for batteries in electric vehicles like locomotives to detect battery health and predict failure. The system uses a data acquisition unit with separate modules for measuring battery voltage, current, and temperature. It connects to the battery terminals and samples the voltage cyclically. The data is converted and sent wirelessly to external equipment. The modules with current limiting resistors allow selective voltage acquisition by switching. This allows monitoring individual battery cells to diagnose problems.

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Monitoring battery health of a vehicle without discharging the battery to determine if it's degrading or approaching failure. The method involves analyzing the battery voltage immediately after engine start. By comparing the post-start voltage to a baseline, it can indicate battery health without needing to fully discharge the battery. This allows in-vehicle, real-time monitoring of battery health independent of charging and SOC levels.

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Accurate battery monitoring using shunt resistors to measure current and temperature compensation to improve reliability. The method involves measuring the voltage drop across two shunt resistors in series or parallel with the battery bus bar. By converting the voltage drops to digital values and applying calibration data, it calculates the current through each shunt. This compensated current difference indicates the battery state. Temperature compensation uses predicting the shunt temperature rise based on current and time. Synchronization ensures fast currents are measured at the same time.

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Battery monitoring system that enables synchronous acquisition of voltage and current data from batteries using wireless communication without wired connections. The battery monitoring device sends a voltage measurement instruction wirelessly to the battery measuring devices at regular intervals. The battery measuring devices acquire voltage and current simultaneously when they receive the instruction. The battery monitoring device receives the voltage data wirelessly and the current data from the battery measuring devices via wireless communication. This allows synchronous acquisition of voltage and current data without needing wired connections.

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