I – Our vision:
In the pursuit of sustainable energy solutions, optimizing the entire lifecycle of batteries has become increasingly important. A transformative approach to achieving this involves integrating a matrix of sensors directly within batteries. This sensor matrix—including temperature, pressure, current, and voltage sensors—remains embedded in the battery throughout its entire life, continuously collecting and storing vital operational data. This innovation not only enhances performance and safety during the battery’s initial use but also significantly streamlines the assessment process for second-life applications, leading to substantial cost savings.

II – Why Sensor Matrix?
Embedding a sensor matrix within batteries creates a robust monitoring system that records essential data from the moment of manufacture through to end-of-life. The Sensors should meet the batteries industries safety reequipments (UL 1642 – Standard for Lithium Batteries, IEC 62133-2:2017, SAE J2464 and SAE J2929, etc.). This persistent data collection includes:

1 – Temperature Monitoring (operational and under testing): Continuously tracking thermal conditions is essential to prevent overheating, avoid charging under freezing conditions, maintain optimal performance, and prevent thermal runaway in lithium-ion batteries. Temperature sensors used in the lithium-ion battery industry must monitor temperatures from -20°C to 200°C to ensure performance and safety. Additionally, these sensors should have a lifespan of around 10 years to match the expected service life of the battery systems they monitor. This range covers:

Normal Operation: Between 15°C and 35°C, requiring an accuracy of ±0.5°C.

Early Warnings of Freezing and Overheating: From -20°C to 60°C, where initial signs of thermal issues may occur, including the risks associated with low-temperature charging.

Detection of Thermal Runaway Conditions: Up to 200°C, requiring an accuracy of ±1°C to identify hazardous temperature escalations.

2 – Pressure Monitoring (under development): Continuously tracking internal pressure is crucial for early detection of battery failures, such as gas buildup from overheating, overcharging, or internal short circuits. Pressure sensors used in lithium-ion battery systems must monitor pressures from 0 kPa to at least 1,000 kPa (0 to 10 bar) to ensure performance and safety. This range covers:

Normal Operation: Internal pressure is close to atmospheric pressure, approximately 100 kPa (1 bar).

Early Warning Range: Pressure increases up to 500 kPa (5 bar) may indicate gas generation and potential safety concerns.

Critical Pressure Levels: Pressures exceeding 1,000 kPa (10 bar) can trigger safety mechanisms like pressure relief vents or lead to cell rupture.

These sensors should have sufficient accuracy +/- 1 % over the whole measurement range. to detect small pressure changes, a lifespan of around 10 years, and be compatible with the battery environment in terms of size, operating temperature range, and chemical resistance.

3 – Voltage and current monitoring (available and under testing):

Accurate voltage and current monitoring are crucial for the safe operation of lithium-ion batteries, as they help prevent overcharging, over discharging, and excessive current flow that can lead to battery degradation, reduced performance, or safety hazards like thermal runaway. Voltage monitoring should cover each cell’s operational range from approximately 2.5V (discharge cut-off voltage) to 4.25V (charge cut-off voltage), with a measurement accuracy of ±10 mV per cell to ensure safe limits and proper cell balancing. Current monitoring must handle the typical operating currents—which vary by application—and detect overcurrent conditions by activating protection when discharge currents exceed the manufacturer’s specified maximum (often set at 2C to 3C) or when charging currents exceed 1C; an accuracy of ±1% of the measured value is essential for calculating the state of charge and ensuring safety. Sensors should be integrated into a Battery Management System (BMS) that monitors individual cell voltages and pack current, balances cells to maintain uniformity, and provides protective actions, all while operating reliably within the battery’s temperature range and complying with relevant safety standards like UL 2054, IEC 62133, and ISO 26262.

By monitoring and maintaining a comprehensive history of these parameters, the sensor matrix offers more rebuts safety system and provides invaluable insights into the battery’s health and usage patterns throughout its first life.

III – Facilitating Efficient Second-Life Battery Assessment:
When batteries complete their initial service—such as powering electric vehicles—they often retain significant capacity, making them suitable for less demanding applications like stationary energy storage. However, assessing the remaining useful life and performance potential of used batteries can be challenging without detailed historical data.

The integrated sensor matrix addresses this challenge by:

Providing Comprehensive Usage Histories: Detailed records enable accurate assessments of the battery’s State of Health (SoH) and remaining capacity, including information about sensors log that can affect performance and safety.

Enhancing Safety Evaluations: Access to historical sensors data ensures the battery has operated within safe limits, reducing risks in secondary applications.

Streamlining Testing Procedures: With readily available data— for example, including pressure fluctuations—the need for extensive diagnostic testing is minimized, accelerating the assessment process.

This information simplifies decision-making for repurposing batteries, ensuring that only suitable units are selected for second-life uses. It not only improves the efficiency of the assessment process but also reduces associated costs.

This approach is crucial for industries aiming to enhance sustainability and reduce costs. As we transition toward a future where energy efficiency and responsible resource management are paramount, the integration of sensor matrices will present a vital strategy. This technology not only maximizes the value extracted from batteries but also plays a pivotal role in advancing sustainable energy solutions and promoting a circular economy.