12 patents in this list

Updated: July 22, 2024

The need for efficient energy storage in electric vehicles (EVs) is ever-growing, but maintaining optimal performance hinges significantly on temperature management. Elevated battery temperatures can lead to safety issues and reduce the lifespan of EV batteries.

This article delves into advanced thermal imaging techniques to monitor and control EV battery temperatures, a critical aspect for enhancing battery efficiency and safety.

Through innovative thermal imaging solutions, we anticipate improvements in battery reliability, extended vehicle range, and safer operation, driving the future of electric mobility towards greener and more efficient transportation.

1.  Proactive Thermal Runaway Detection and Isolation System for EV Batteries

GM Global Technology Operations LLC, 2023

Detection and mitigation of thermal runaway propagation in a vehicle battery to prevent battery damage and safety hazards. The system uses sensors like gas, temperature, and infrared inside modules to detect conditions leading to thermal runaway. If thresholds are exceeded, active relays isolate the faulty module to stop propagation. The battery management system coordinates this based on sensor data. This allows proactive isolation before runaway instead of waiting for voltage/temp indicators.

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2.  Advanced Thermal Imaging for Non-Contact Temperature Monitoring in EV Batteries

Dr. Ing. h.c. F. Porsche Aktiengesellschaft, 2023

Traction battery for electric vehicles that uses IR sensors with deflection optics to provide improved temperature monitoring. The battery has IR sensors with arrayed elements that can spatially resolve temperature over surfaces. A deflection optic between the sensor and surface allows detection without contact. This allows larger battery packs with higher packing density since the optics can map a large area onto the sensor without needing large gaps. The optics are positioned outside the battery module housing with openings for IR beams to detect internal cell surfaces.

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3.  Non-Contact Temperature Sensing for Electric Vehicle Charging Connectors Using Thermal Imaging

TE Connectivity Solutions GmbH, 2023

Remote and isolated temperature sensing of electrical terminals like charging connectors without adding thermal mass or resistance. It involves applying a thin temperature-sensitive material patch to the terminal surface and sensing changes in the patch using an isolated external circuit. This allows detecting terminal temperature without contact or affecting its electrical properties. The patch has low thermal mass compared to the terminal. Techniques like photodetection or magnetic sensing can be used. The patch materials expand or lose eddy currents at higher temperatures, which can be detected remotely to determine safe operating temperatures.

4.  Infrared Sensor-Based Monitoring for Early Detection of Thermal Runaway in High-Density Battery Packs

Amazon Technologies, Inc., 2023

Preventing sudden battery failure in high-density battery packs for electric vehicles, UAVs, etc. by sensing precursor conditions to thermal runaway at the level of individual battery cells. Infrared sensors are used to monitor entire rows of battery cells without requiring individual instrumentation on the cells. The infrared sensors detect temperature changes in the cells to anticipate thermal runaway with sufficient time to prevent sudden battery failure, or to detect and isolate thermal runaway to a particular cell to minimize damage. This allows direct, immediate monitoring of all the cells without cluttering the enclosure or requiring wiring to each cell.

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5.  Real-Time Internal Battery Temperature Estimation in EVs Using Thermal Network Modeling

BYD COMPANY LIMITED, 2023

Real-time estimation of internal battery temperature in electric vehicles when traditional temperature sensors fail. The method involves constructing an equivalent thermal network model of the battery using offline testing data. Optimal parameters are determined using a multi-objective fitting function. During vehicle operation, the initial battery state and first operational data are used along with the model to estimate the internal temperature. Feedback corrections are made to improve accuracy. This allows estimating the battery's internal temperature in real-time when external sensors fail.

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6.  Infrared Thermal Imaging for Precise Temperature Monitoring in EV Battery Cells

Bayerische Motoren Werke Aktiengesellschaft, 2022

Improving temperature monitoring of a battery pack for electric vehicles to quickly and accurately detect and locate temperature increases in individual cells. The solution is using a common infrared matrix sensor positioned near the cells with a view encompassing the cell surfaces. This allows capturing thermal images of the cells. By analyzing the signals from the sensor's sub-regions, temperatures of each cell can be determined and any temperature increases precisely assigned to the corresponding cell. This provides better and faster temperature monitoring compared to external sensors with varying detection times.

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7.  Infrared Sensor Array for Early Detection of Temperature Anomalies in High-Density Battery Packs

Amazon Technologies, Inc., 2022

Battery pack design and monitoring technique to prevent sudden battery failure and thermal runaway in high-density battery packs used in electric vehicles, drones, and other high-power devices. The technique involves using infrared sensors to monitor temperature changes within the array of battery cells without requiring individual instrumentation on each cell. The infrared sensors are arranged in a string or mesh configuration that is routed through the battery pack. They detect sudden temperature spikes in individual cells before the overall battery temperature rises, allowing early intervention to prevent thermal runaway and isolate failing cells. This provides more reliable and proactive thermal management compared to spaced sensors or relying on overall pack temperature.

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8.  Infrared Sensor-Based Foreign Object Detection for Wireless Power Transfer Systems

QUALCOMM Incorporated, 2018

Detecting foreign objects in the critical space around a wireless power transfer system to prevent overheating and safety hazards. The detection uses infrared (IR) sensors to sense object temperatures. Time differentiators are used to generate signals based on temperature changes. Correlation with the varying exposure level magnetic field indicates objects in the critical space. This allows detecting foreign objects before they reach critical temperatures. It provides contactless foreign object detection in the critical space around a wireless power transfer system using IR sensors and time differentiators.

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9.  Infrared-Based Non-Contact Temperature Sensing for Electric Vehicle Battery Packs

Robert Bosch Battery Systems LLC, Robert Bosch GmbH, 2016

A non-contact temperature sensing system for battery packs that eliminates the need for contact-based temperature sensors. It uses infrared sensors mounted on a PCB inside the battery pack. The IR sensors are positioned to view the emitted IR radiation from the cell surfaces without touching them. A controller interprets the IR signals to determine cell temperatures. This provides accurate temperature monitoring without the complexity and potential reliability issues of contact-based sensors.

10.  Advanced External Temperature Monitoring System for Electric Vehicle Batteries

MAGNA STEYR Battery Systems GmbH & Co OG, 2014

Battery system with improved temperature monitoring for reliability and safety. The system uses infrared temperature sensors located on the electronic unit, rather than inside the battery cells. This allows measuring the temperature of specific regions on the cell surfaces. Multiple sensors are placed at spaced-apart positions to avoid overlap. The sensors are decoupled from the cell heat by insulation. This provides better temperature mapping compared to internal sensors, which can have thermal transfer issues. The sensors can also have windows in the cells to detect internal temperature rises.

11.  Optical Pyrometer-Based Detection of Thermal Events in EV Battery Cells

Tesla Motors, Inc., 2011

Early detection of thermal events in battery cells of an electric vehicle to prevent propagation and mitigate thermal runaway. The method uses optical pyrometers inside the battery module to detect increased shortwave radiation emitted by a cell reaching a critical temperature. This allows intervention like full cooling or reducing power demand before full runaway. Placing pyrometers anywhere in the module enables detection since radiation from all cells reflects off inner surfaces.

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12.  Contactless Thermal Imaging for Universal EV Battery Charging Safety

William Stephen Hart, Brian L. Graham, John Arthur Fee, 2008

Contactless temperature monitoring of battery packs during charging using thermal imaging to enable universal chargers that work with batteries from different manufacturers. The thermal imaging sensors are placed near the battery packs to measure their temperatures without contact. The sensors can detect hot spots, temperature gradients, and changes to identify overheating risks. This allows monitoring battery temperatures during charging to prevent overcharging or venting. The imaging data can also be used to calculate state of charge and health. By using contactless thermal imaging, it provides a standardized way to monitor battery packs for charging safety across different battery brands.

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