18 patents in this list

Updated: July 22, 2024

Accurate temperature monitoring is crucial for the performance and longevity of electric vehicle (EV) batteries. Inadequate temperature management can accelerate battery degradation, shorten battery lifespan, and compromise vehicle safety.

This article delves into the use of optical sensors for monitoring EV battery temperature, an innovative approach that is pivotal for ensuring optimal battery performance and safety.

With advancements in optical sensor technology, we can achieve precise temperature monitoring, which enhances battery efficiency, extends lifespan, and improves safety, driving forward the next wave of innovation in electric vehicle thermal management.

1.  Optical Sensor-Based Temperature Monitoring for Energy Storage Systems

LS ELECTRIC CO., LTD., 2024

Temperature measurement device for energy storage systems like battery storage that can measure temperatures both inside and outside the battery modules. It uses an optical fiber cable with spaced sensing spots to measure temperatures at intervals between modules. Additional outer sections connect the inner sections between stages. This allows monitoring temperatures between modules as well as inside the modules. The cable fixing units secure the cable between stages.

2.  Non-Invasive Optical Sensor System for EV Battery Temperature Monitoring

GM GLOBAL TECHNOLOGY OPERATIONS LLC, 2024

Battery module temperature measurement system using optical sensors to non-invasively measure cell temperatures without contact. The system involves placing sensors in the module frame that can make line-of-sight temperature measurements through apertures in the frame to the battery cells. A cell monitoring unit processes the sensor readings to generate accurate cell temperatures. This allows quick, accurate, and non-invasive temperature monitoring of battery cells without contact, minimizing disruption to the cells.

3.  Optical Temperature Sensing for Electric Vehicle Battery Monitoring

Kistler Holding AG, 2023

Optically operating temperature sensor for measuring surface temperatures of components like battery cells in electric vehicles without using electrical connections that could increase risk of short circuits. The sensor uses fiber optics with spaced-apart elements inside a rigid protective element that connects to the component surface. External forces are absorbed by the protective element, preventing deformation of the fiber and false temperature readings. The fiber's thermal expansion detects temperature changes.

4.  Thermo-Fluorescent Optical Fiber Sensor for Precise Battery Temperature Monitoring

COMMISSARIAT À L'ENERGIE ATOMIQUE ET AUX ENERGIES ALTERNATIVES, 2023

Thermo-fluorescent optical fiber sensor for measuring temperatures in applications like batteries. The sensor uses a thermo-fluorescent optical fiber with a layer containing thermo-fluorescent particles at one end or along the length. The particles emit light when heated and can be imaged through the fiber. The particles are held in place by a photo-polymerized matrix. The fiber is made by depositing the thermo-fluorescent particles, followed by the photo-polymerizable system, then curing to polymerize the matrix. This provides controlled distribution of the particles in the matrix for optimal sensor performance.

5.  Distributed Temperature Monitoring in Battery Modules Using Optical Fiber Technology

LS ELECTRIC CO., LTD., 2022

An optical fiber temperature measurement system for power devices like battery modules to enable distributed temperature monitoring. Optical fiber cables are installed inside each module and connected to an external control unit. The cables contain fiber optics that can measure temperatures based on Raman scattering. This allows accurate temperature monitoring inside each module as well as between modules by connecting the fiber ends.

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6.  Fiber Optic Sensor System for Comprehensive EV Battery Monitoring

Wuhan Unviersity of Technology, 2022

Online monitoring system for batteries using fiber optic sensors to simultaneously measure multiple parameters like temperature, strain, pressure, voltage, current, and gas composition inside batteries in a closed, corrosive environment. The sensors are based on fiber Bragg gratings (FBG) that can be multiplexed and connected in series on a single fiber. This allows distributed, integrated, and distributed monitoring of batteries, modules, clusters, and systems. The FBG sensors have ultra-low reflectivity to enable high capacity multiplexing. A FBG demodulator reads the signals and transmits them to a computer. The FBG sensors are connected inside the battery using optical fiber connectors. This provides compact, corrosion-resistant, and electromagnetic interference-resistant monitoring without wiring complexities.

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7.  Remote Analysis of EV Battery Parameters via Onboard Optical Sensing

VIAVI SOLUTIONS INC., 2022

Optimizing electric vehicle battery monitoring using separate onboard data collection and remote data analysis. A data collection device in the vehicle detects battery parameters like temperature and strain using fiber optics. The collected data is sent wirelessly to a remote analysis center for processing. This allows using existing vehicle electronics for data collection without needing dedicated hardware. The remote analysis enables efficient centralized processing of data from multiple vehicles, reducing onboard computational requirements.

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8.  Optical Fiber-Based Sensing Membrane for Non-Invasive Monitoring of EV Battery Conditions

VIAVI SOLUTIONS INC., 2022

Embedding optical fibers in a flexible substrate to create a sensing membrane that can be attached to devices like batteries to monitor thermal, mechanical, and radiation properties without directly embedding the fibers in the device. The substrate thickness and material properties are chosen to accurately sense device properties when the membrane is either embedded in the device or attached to its surface. This allows monitoring temperature, strain, vibration, etc. of devices like batteries without complex fiber routing through each component.

9.  Optical Fiber-Based Sensing Membrane for Comprehensive Device Monitoring

VIAVI SOLUTIONS INC., 2022

An optical fiber-based sensing membrane for monitoring temperature, strain, vibrations, and radiation in devices like batteries, nuclear power plants, and defense equipment. The membrane has integrated optical fibers embedded in a flexible substrate with a specified layout pattern. The layout compensates for spatial resolution and fiber losses. This allows accurate sensing of localized temperature, strain, etc. without needing individual fiber connections. The membrane can be applied directly to device surfaces or embedded in molded parts. It enables compact, flexible, and scalable sensing compared to embedding single fibers.

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10.  Optical Sensor Integration for Real-Time Monitoring of Lithium-Ion Battery Health Parameters

Zhejiang University, 2022

Lithium-ion battery with implanted optical sensor for monitoring battery health parameters. The battery has a sensing element that can monitor internal battery parameters like gas composition, temperature, and pressure. An optical fiber is used to connect the sensing element to an external demodulation module. The fiber is inserted into the battery and sealed. This allows internal sensing without removing the battery. The fiber connects to a demodulation module outside the battery to analyze and process the sensor signals. The demodulation module can be connected to equipment for further analysis.

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11.  In-Situ 3D Printed Optical Sensors for Real-Time Monitoring of Li-ion Battery Parameters

Aleksandra Fortier, 2022

Embedding optical sensors inside Li-ion battery cells using 3D printing techniques to provide real-time monitoring of cell-level parameters like temperature, state of charge, and state of health. The sensors are printed using a silica-based ink that cures in-situ. The sensors are located on the separator layer between the electrodes. This allows direct measurement of internal conditions without invasive techniques. The 3D printing enables precise placement of the sensors without impacting cell performance. The optical sensors have inert properties that can withstand the battery environment.

12.  Optical Sensing Technology for Real-Time EV Battery Condition Monitoring

Sanyo Chemical Industries, Ltd., APB Corporation, 2021

A secondary battery module with integrated optical sensing for monitoring cell characteristics and condition. The module has a battery pack with cells stacked inside. Each cell has a light-emitting unit to generate an optical signal based on cell voltage and temperature. An optical waveguide covers the cells and extends over them. The waveguide has a common path for the optical signals to propagate. This allows optical sensing of all cells in the pack without wiring connections. An exterior body contains the pack and waveguide. A light-receiving unit away from the pack receives the propagating signals to determine cell conditions.

13.  Optical Fiber Sensor System for High-Resolution Temperature Monitoring in EV Batteries

INPHOTECH SP. Z O.O, 2021

Temperature monitoring system for early detection of vehicle fires, particularly in the engine compartment or battery compartment, using fiber optic sensors. The system has a light source with a tunable wavelength, an optical fiber interferometer, and a detector connected to a signal processing module. The light source is pulsed with a short periodic waveform to scan the fiber length. The interferometer detects temperature changes along the fiber. By sweeping the wavelength, sub-centimeter resolution is achieved. This allows highly localized temperature monitoring near components like batteries and pumps. Alarms are triggered when temperatures exceed thresholds at specific points.

14.  Optical Temperature Sensing for EV Charging Connectors with Minimal Thermal Mass Impact

TE CONNECTIVITY CORPORATION, 2020

Remote and isolated temperature sensing of an electrical terminal like an EV charging connector without adding thermal mass or electrical resistance to the terminal. The method involves applying a thin patch with low thermal mass to the terminal surface and sensing changes in the patch using an isolated external circuit. The patch allows isolation without adding thermal mass like embedded sensors do. The patch can have magnetic particles that expand/contract with temperature, or a photodetector reflecting light from the terminal.

15.  In-Situ Monitoring of Lithium-Ion Batteries Using Embedded Optical Fiber Sensors

Palo Alto Research Center Incorporated, 2019

Embedding optical fiber sensors inside electrodes of lithium-ion batteries to enable real-time, in-situ monitoring of internal parameters like temperature, stress, strain, concentration, chemistry, and gas presence. The fiber optic cables with sensors are placed between the current collector and electrode material layers during battery manufacturing. This provides more accurate and stable sensor signals compared to external methods. The embedded sensors enable better characterization of individual anode/cathode electrodes versus average cell values. The sensors can also detect electrode failures earlier.

16.  Real-Time Internal Monitoring of EV Batteries Using Embedded Fiber Optic Sensors

Palo Alto Research Center Incorporated, 2016

Embedding fiber optic cables with sensors inside electrodes of lithium-ion batteries to monitor internal conditions like temperature, strain, and chemistry in real-time. The fiber optic cables are positioned on current collectors and then the electrode material is deposited over them. This allows accurate, individual electrode-level sensing without external measurements. The embedded sensors provide insights into electrode behavior and failure mechanisms. It enables more accurate state-of-charge (SOC) and state-of-health (SOH) estimation compared to external measurements alone. The embedded sensors also aid in understanding battery accidents by providing quicker, more precise failure location information.

17.  Optical Pyrometer-Based Thermal Event Detection in Electric Vehicle Batteries

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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18.  Optical Pyrometer System for Early Detection of Thermal Runaway in EV Battery Cells

Weston A. Hermann, 2008

Early detection of thermal runaway in battery cells to prevent propagation and catastrophic failure of entire battery packs. The system uses optical pyrometers inside the battery module to detect cells heating above a threshold. By detecting individual cell overheating early, mitigation measures like active cooling or reduced load can be applied before it spreads. The pyrometers sense short wave radiation emitted by overheating cells in the packed module. Placing them anywhere allows detection since radiation from all cells reflects in the module.

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