Can Battery Powered IoT Devices Cause a Fire?
We received this question from a client and thought it might be worth sharing our perspective:
Client: My understanding is that battery powered IoT devices have traditionally avoided using lithium because of the potential fire risk if damaged or improperly packaged. Can battery powered IoT devices cause a fire?
A couple of things to note about batteries in general. There are 3 different situations that can cause a battery related fire:
Short Circuit is the most common way fires are started and applies to both alkaline and lithium.
This generally happens when batteries are installed the wrong way or when the devices are tampered/damaged with.
Both these are avoidable by electronic design via thermal fuses and reverse voltage protection circuitry.
Piercing occurs when a device is crushed or when sharp objects puncture through them. This is applicable to both types of batteries and is highly unlikely to occur.
When too much current is drawn from the batteries, this breaches the battery’s maximum continuous pulse.
These batteries are designed to provide power to electric motors and the IoT devices we use them in does not draw 1/10th of the amount of power they are typically used for.
Primary cells vs Rechargeable cells
Primary cells are batteries that cannot be recharged and can only discharge once, which is the case with both alkaline and Lisoc Batteries (Lithium thionyl chloride Battery).
Rechargeable battery cells are the problem and account for 90% of Lithium Ion or Lithium Polymer related fires due to the fact that they often get overcharged or are not properly monitored by the design circuitry.