major tire manufacturerR&D division

Hi-Tech Battery Holds Key to Next-Generation Tire Pressure Monitoring SystemBattery limitations hamper quest for low-profile, lightweight, and heat-resistant sensor

Background

Modern cars are fitted with TPMS (Tire Pressure Monitoring Systems) to measure their tire pressure. Advances in automotive technology mean that in future, these sensors will be required to do more than just provide information on the tires themselves, such as tire pressure and tire wear. Since the tires are the only part of the car that makes contact with the road, future sensors will also require to monitor and feedback information on the condition of the road surface, such as temperature, wetness and icing to the car’s control systems. The client’s R&D team was racing to develop a next generation sensor.

Problems

Competition Intense in Search for Effective Sensor

The R&D team wanted to build a compact and lightweight next generation tire sensor that used the manufacturer’s own TPMS technology. However, the process of miniaturization and weight reduction created battery mounting issues. The need to mount the battery in a dedicated holder meant that the sensor’s footprint and weight could only be reduced to certain size and weight. To make things worse, just as the team was trying to solve this problem, they learned that a competitor was planning to develop a similar sensor with almost identical functionality. Hearing this, the management ordered the team to make their sensor 10% smaller and lighter than the competitors. The task had just got even more challenging.

Power-Hungry Features Cause Headaches

As the project progressed, the team discovered yet another problem. Now equipped with additional features, the sensor required more power and energy than the existing sensors using a conventional non-rechargeable (primary) battery. Since next-generation sensors need to be able to communicate wirelessly, the team also considered using a rechargeable battery, but they could not find a candidate that was sufficiently small, light, and heat-resistant. Furthermore, since none of the battery manufacturers were able to provide the one-stop solutions regarding power generation and transfer technologies that would be required to effectively charge the battery to be used for the sensors, the team needed to consult a range of service providers. Not making any progress, the team was worn out.

Main Issues

  • The way the battery was mounted on the sensor made it difficult to make the tire sensor smaller or lighter.

  • Conventional non-rechargeable (primary) batteries could not provide sufficient current or capacity to run a multifunction sensor. Meanwhile, no rechargeable alternative that was sufficiently compact, lightweight and heat-resistant could be found.

  • Battery manufacturers did not offer the kind of “one-stop” solutions for effective generation and power transfer solutions that would be required to charge such a rechargeable battery.

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