Query:
I am currently developing a humidity sensor-based wireless sensor node powered by a lithium thionyl chloride (LiSOCl₂) battery. The goal is to operate the sensor for 5 to 10 years without replacing the battery. To monitor the remaining battery life, I plan to integrate a fuel gauge IC.
The sensor is active for 20 ms during each measurement cycle and remains in sleep mode for the rest of the time. The measurement interval can be 5, 10, or 15 minutes. The active current of the sensor module is 20 mA, and the sleep current is 60 µA.
In each transmission, I would like to send both the humidity reading and the remaining battery level in percentage.
I have the following questions:
- Will I be able to monitor the remaining battery life in percentage or State of Charge (SOC)?
- Can the fuel gauge IC enter sleep mode during the sensor’s sleep period without compromising accuracy?
- I require very low active and sleep current from the fuel gauge.
Is the LTC3337 suitable for this application? If not, could you recommend a more appropriate fuel gauge IC that meets these requirements?
Thank you.