Innovations in Battery Management Systems for Electric Vehicles

Secondary battery system with connected battery modules that each have a heating device. The system controller determines the power supplied to each module's heater so that modules with higher SOC or charge receive more heating power. This balances the charge levels between modules by consuming excess energy from higher charged modules. The controller also activates heating based on temperature, SOC, or charge levels. This reduces SOC and charge imbalances between modules while minimizing wasteful power consumption. The system can be used in electric vehicles to maintain module performance and longevity.

Battery balancing system that isolates individual cells from a stack to prevent overcharging or over-discharging. The system uses inline and outline switches to electrically connect/disconnect cells. When a fault is detected, the system isolates and monitors suspect cells. If the fault reoccurs, the cell is permanently isolated. This proactive balancing prevents cell damage and improves stack performance compared to passive or active balancing.

Controlling battery systems in electric vehicles to enhance battery lifetime, energy utilization, and performance by dynamically allocating voltages to individual battery modules. The battery modules are connected in series through power electronics converters. The method involves setting initial module voltages to distribute the total battery voltage equally across modules. Then, monitoring module states like temperature and charge level and adjusting module voltages proportionally to balance the modules based on their conditions.

Battery system for electrically powering an end device with multiple battery packs that have identical electrical components and can dynamically assign one as the master to control discharging/charging.

Cell balancing device for a battery pack with connected battery cells. It uses parallel discharge circuits with switches and resistors to balance cell capacities. The discharge circuits are controlled by a processor. A watchdog monitors the processor and resets it if it malfunctions. When the vehicle ignition is off, the processor enters a sleep state where it balances cells. To reduce current and prevent watchdog resets, the processor limits the number of simultaneously discharged cells.

In a battery module using a simple, robust and inexpensive balancing scheme to maximize energy and lifetime of the battery string. The scheme avoids using a processor to actively balance cells. It compares voltages of cells in a string using a voltage comparison circuit. Then it transfers energy between the highest odd cell and lowest even cell, and highest even cell and lowest odd cell, until voltages are balanced.

Method for balancing charge in battery cells of a multi-cell battery pack like those used in electric vehicles. The method uses a battery controller that monitors cell voltages. The controller compares the voltage spreads between cells to a threshold. If the spread exceeds the threshold, it triggers a balancing routine that selectively charges or discharges cells to bring them back into balance.

Battery balancing system for lithium-ion cells in a battery module that balances cells without storing individual cell balancing times. The system uses a control unit to select a reference cell and target group of cells based on their state of charge (SOC). It calculates a balancing time based on the SOC difference and then performs balancing only on the target group during that time. This reduces the memory and processing needs compared to storing balancing times for each cell.

Systematic approach to monitor and control a vehicle battery pack for optimal performance and lifetime by using cell switching. The method estimates the battery state via voltage, temperature, and current measurements. It predicts future power needs using GPS data. The system then optimizes the battery cell activation pattern to meet those needs while balancing cells and avoiding thermal limits. It uses switching units on each cell to vary series/parallel connections.

Method for determining an SOC of a battery that improves accuracy of SOC estimation for batteries, especially those with a hysteresis characteristic. It involves obtaining the current OCV value of the battery and the cumulative continuous charging or discharging capacity. Based on these, it determines credible ranges of possible SOC values and uses these to correct the SOC estimate. This improves accuracy by accounting for the battery's hysteresis and historical charge/discharge behavior.

A diagnostic method for accurately detecting uneven SOC (state of charge) in a secondary battery electrode, indicative of localized degradation. By monitoring the change in open circuit voltage (OCV) with temperature, and comparing it to reference data, uneven SOC conditions can be detected. If an inflection point appears in the OCV vs SOC graph, it indicates electrode surface unevenness and degradation.

Battery management system for electric vehicles that can detect a low voltage cell among the many cells in a battery pack. The system compares the state-of-charge (SOC) of each cell before and after a vehicle service period. If a cell has a significant SOC decrease compared to others during vehicle shutdown, it indicates a low voltage cell.

A more accurate method to estimate battery state of charge (SOC) without needing long open-circuit periods. The method involves: 1) Determining a near-steady-state battery model to characterize OCV change over shorter periods. 2) Using this model to estimate steady-state OCV after a shorter period. 3) Using the steady-state OCV to determine SOC without needing a long open-circuit period.

Estimating the state of charge (SOC) of a secondary battery with hysteresis in order to improve SOC estimation accuracy. When the open circuit voltage (OCV) of the battery is within the voltage range where hysteresis occurs, the battery is charged with an amount of power larger than a prescribed amount to temporarily eliminate the hysteresis. Then the SOC is estimated by obtaining the OCV after charging and referring to a charging curve.

Estimating the remaining useful life (RUL) and cumulative wear of an electric vehicle battery to optimize battery life, performance and cost. The method involves periodically monitoring battery parameters like state of charge (SOC) and health, using that data to estimate degradation parameters like capacity loss and internal resistance, and then using those estimates to predict RUL and cumulative wear. This allows proactive optimization of battery usage to extend its lifetime.

Improved battery health estimation that can provide more accurate and reliable state of health (SOH) estimation of batteries, such as EV batteries, without requiring expensive equipment like impedance spectroscopy. The approach involves obtaining parameters from battery charging data that capture changes in the battery's response function. By tracking changes in these parameters over time, the SOH can be estimated.

Monitoring battery cell health and electrolyte properties using external conductive portions on the battery enclosure. The conductive portions are attached to the cell's outer surface and capacitance measurements are taken between them and internal conducting structures like cell terminals. These capacitance values are used to assess battery health, electrolyte level, remaining life, and identify thermal runaway.

Compute battery capacity degradation metric without removing the battery from the device. It measures the charge energy loss of the battery during charging/discharging using current and voltage sensors. This loss is compared to a reference battery to compute degradation.

Method for predicting the State of Health (SOH) of a battery in real-time during charging/discharging. The method uses periodic dQ/dV measurements during charging to predict SOH without needing full discharge cycles. A lookup table of dQ/dV values and corresponding SOH levels is created based on completely discharged cycles of a reference battery. The lookup table is then used to extract the predicted SOH from the measured dQ/dV values of the actual battery.

Method for estimating the state of health (SOH) of a battery that is application-independent. The method involves monitoring the battery terminal voltage under specific conditions and comparing it to terminal voltage test data. The terminal voltage provides a surrogate for battery capacity. By comparing the terminal voltage to test data, an estimate of the battery's SOH can be obtained.

A method and apparatus for estimating the state of health (SOH) of a power battery pack in an electric vehicle. The method involves obtaining the charging curve of a cell in the pack and determining the charging stage. Then it calculates the remaining capacity of the cell from the pack voltage levels at specific points in the charging stage. Finally it uses the remaining capacity to estimate the SOH of the cell. This provides a more convenient and accurate way to estimate battery pack health compared to methods relying on measuring amp-hour throughput.

Analyzing the state of health (SOH) of a battery to determine if it can be reused in secondary applications like energy storage after its initial use in electric vehicles. The method involves comparing battery temperature profiles during discharge to measure degradation. This is done by measuring battery temperature as it discharges from full charge to quantify the rate of temperature increase in the second half of the discharge cycle. The increase rate is compared to a reference battery to determine the degree of degradation.

Electrode-specific estimation of lithium-ion battery state of health to determine the capacity and utilization range of each electrode.

A method for safely charging a traction battery in electric vehicles to avoid overcharging and potential safety issues. The method involves monitoring battery parameters like state of charge (SOC) during charging, and discharging or stopping charging when the parameter changes by a certain threshold. This prevents continuous charging if the battery is already full, preventing overheating, lithium plating, and other problems.

Electrified vehicle thermal management system that enables optimized cooling and heating of the battery pack and other components while avoiding overcooling. The system uses a valve to selectively direct coolant flow through a bypass loop or the battery pack based on heat rejection from a charge air cooler. This prevents overcooling by bypassing the battery when the coolant is already hot from the air cooler.

Battery pack structure for electric vehicles that improves temperature uniformity and heating control with a heating plate enclosed in a heating unit. The battery pack has a heating plate that surrounds the battery cells and a separate heating unit that encloses the heating plate. This provides better temperature uniformity and heating compared to directly attaching heaters to individual cells. A control unit monitors the battery temperature and operates the heating unit as needed.

Battery module that manages heat according to external temperature to prevent power degradation in cold environments. The module includes a housing containing battery cells, busbar frames covering the cells, end plates sealing the housing, and a thin film layer between the busbar frame and end plate. The film layer automatically heats up in cold temperatures to warm the cells and prevent power loss.

Battery temperature adjustment to maintain performance while reducing energy consumption when parked for extended periods. The system checks scheduled parking time and only adjusts battery temperature if it's shorter than a threshold. This avoids using battery power to maintain temperature during long parking periods when the vehicle is unlikely to be used.

Efficiently controlling the temperature of an electric vehicle battery to improve charging efficiency by determining the optimal charging temperature based on vehicle driving conditions and battery charge status, and then adjusting the battery temperature to that optimal level before charging.

Battery temperature adjustment system for electric vehicles to prevent battery deterioration. The system has a battery, cooling device and control system. When the vehicle is connected to an external power source, the control system selects either the battery or external power to cool the battery based on a deterioration sensitivity map. If cooling with external power would cause more deterioration than using battery power, it cools with battery power.

Using the electric motor of an electric vehicle's drive unit to heat the battery. The controller receives a battery heat request value and torque command. It generates a motor command that delivers heat to the battery to achieve a target temperature, while also causing the motor to operate at the requested torque. This allows heating the battery at any time, not just during charging, to improve EV operation and battery longevity. The motor command is manipulated to balance torque and battery heat.

Battery temperature sensing method for electric vehicle batteries that reduces complexity and cost compared to conventional methods. It uses a grid of thermally-connected diodes on a flexible circuit layer that can be wrapped around battery cells. The diodes act as temperature sensors by measuring voltage drops. By selectively grounding one side of the grid, the diode temperatures can be determined. This spatially-resolved temperature measurement provides better insight into battery cell health and performance compared to traditional methods that use a few discrete sensors.

An efficient and cost-effective vehicle battery temperature control system that uses existing vehicle parts and components to regulate battery temperature. The system uses a blower fan and ducts to introduce outside air for cooling or heated air from the exhaust pipe to warm the battery compartment. The blower fan can rotate in two directions, pulling cool air in to lower battery temperature or hot air from the exhaust pipe to raise battery temperature. A temperature sensor detects battery temp and a processor controls the fan direction based on set temperature thresholds.

Working vehicle that prevents over-discharge of the battery when driven while connected to an external power source. The vehicle has a battery, charger, sensor, controller, display, and switch. A battery management system monitors the charger and battery when driven while connected to external power. It switches the vehicle to use the charger power instead of the battery power when the charger is connected and a signal allows driving connected. This avoids over-discharge if the operator forgets to switch manually.

Electric powered working machine that manages battery charging to avoid obstructing work plans while still providing diagnostic battery conditioning charges. The machine has a controller that determines whether to recommend and execute a diagnostic charge with rest periods based on battery history and estimated charge time. This prevents unnecessary and potentially long charges that could disrupt work schedules.

Controlling all-solid-state lithium-ion batteries to improve safety in electric vehicles. The system detects when the battery's state of charge (SOC) exceeds 100% due to overcurrent events. It then reduces the maximum SOC limit to prevent further overcharging. This prevents capacity loss and overheating risks from overcharging.

Controlling capacitors to reduce common mode currents in electric vehicle power converters. The control involves connecting an extra capacitor when the converter is activated and disconnecting it when the converter is inactivated. This prevents parasitic capacitance discharge that causes common mode currents. A pre-charge circuit can also be used to avoid inrush current when connecting the capacitor.

A battery system that can detect the presence of liquid inside the housing of the battery system. The system uses a liquid detector connected to the battery management system. The detector includes a high-voltage conductor that is connected to the bus bars of the battery cells. The conductor extends into a tray located in the housing. If cooling liquid leaks from the battery module, it will collect in the tray and complete the conductivity path to the conductor, triggering the detector. This enables monitoring of the cooling liquid level and verifying if leaked battery coolant is accumulating in the tray.

Power control system for electric vehicles that provides improved protection against faults and overcurrent. It includes parallel contactor and fuse pair called active sacrificial protection device (ASPD) connected in parallel with one of the main contactors. In normal operation, the ASPD contactor remains open. If a fault current exceeds a threshold, the ASPD contactor closes and the main contactor can open while the fuse blows to interrupt the fault. This dynamic fault response provides better protection than just the main contactors.

Intelligent battery system for vehicles that uses distributed management modules in each battery module to monitor and detect faults. The modules communicate with a master module for coordination. If the master module fails, a backup takes over. The distributed fault detection improves safety and reliability by enabling each battery module to monitor itself, detect issues like thermal runaway, and alert the vehicle control system.

Management of the power provided by the batteries in vehicles to ensure that critical systems always have power while conserving battery capacity when the vehicle is not in use. The management involves disconnecting the main vehicle battery from all systems except the ignition when the engine is off. A separate auxiliary battery powers non-essential systems. This preserves the main battery charge to start the vehicle.

Battery management systems (BMS) for electric vehicle batteries that use wireless authentication to securely connect batteries to host vehicles and other devices. The BMS have a short range wireless transceiver that communicates with a matching transceiver in the host platform. The authentication allows mutual identification and authorization of the battery and host. Once authenticated, the BMS enables energy flow and data communication. If not authenticated, the BMS blocks energy transfer and data access. This prevents unauthorized use of batteries and protects against theft when used in shared vehicle services.

A battery management system that allows individual battery cells to communicate their status to a central controller over the existing battery connections, without needing additional wires. The system uses modulation techniques to transmit data signals over the DC power lines connecting the batteries together. The battery cells have monitoring boards that extract, demodulate and decode the data signals to provide individual cell parameters to the central controller. The controller can then adjust battery performance based on the cell data.

Battery module with a relay driver that uses direct current (DC) to control a relay to reduce electromagnetic compatibility (EMC) issues. The relay driver provides a first DC current to close the relay and a second DC current to keep it closed. The second current has different parameters than the first current. This avoids switching the relay coil with pulse-width modulation or constant voltage that causes EMC problems.