A usual question you have when designing a device is the autonomy of your battery and the power consumption of your device. By the past I’ve tried different tools for this usage. Starting with USB sticks power consumption, only working for high consuming devices. They are low precision. Going to multimeter tools with USB connectivity precise but sampling at 3-5Hz only. During a certain time I’ve plan to make a solution on my own and finally I’ve found the OTII tool from QOITECH on the recommendation of friends from Sigfox community.
Here is my experience with that tool.
When making an IoT project the battery choice is something really important. Batteries stands for autonomy, sizing, price and usage conditions.
There is no universal solution to power your device, the right battery really depends on your requirements. To find the right powering solution you need to consider a certain number of parameters. We will try in this post to list most of them. This post is not exhaustive: I’m not a battery expert. This post is based on my own experience and you may consider it as a starting point, not a solution.
As it is a recurrent question to find the right battery for an IoT design, I decided to write a post about this topic. I’m not claiming to be an expert of this and I’ll not give insight on this. The purpose is to list the different technology existing with the main characteristics to be able to use the best fitting technologies quickly.
This post is presenting a table of the different battery’s technologies available with the main characteristics. These characteristics are global one regarding the technology. Each of the battery vendor can have specific specifications a bit different. You will need to take a look on datasheets details.
After writing a post about my experience with LiPo Batteries I’m now proposing a post about NiMh. LiPos are good batteries : not expensive with a good energy density, really easy to manage for charging. For these reason they are used in many electronic designs.
But in some applications they are not enough stable, this is as an example the case for an automotive use where the internal temperature of a car can reach higher temperature than 65°C. This is the limit for LiPos. In my experiences I had some having been destroyed due to warm temperature.
NiMh is not an optimal solution but you can find some batteries capable to support 85°C and resist to +130°C before being destroyed and have a fire risk. Varta V500HT is a good example of battery for a such use.
NiMh is less easy to use than LiPos, this post is detailing my experience.
LiPo (Lithium Polymere) batteries are interesting batteries for IoT as they are nt so much expensive, easy to get with multiple form factors and multiple capacities. As they are used for radioguided planes and such toys, you have a lot of really small batteries available for a couple of euros.
The Lipo battery is typically providing 3.7V. This sounds good for 3.3V circuit. The charging circuit is quite easy and low expensive compare to some others battery technology.
But there is no miracle and a couple of problem I’m actually discovering and this post will introduce.