I’m interested in running some small IOT type devices. They will get cold (-8c) and I’d like them to
a) Not catch fire
b) Work in direct sun in an enclosure 50c
c) Last a really long time
So I’ve got interested in lithium titinate chemistry they are reasonably affordable sometimes mis-described as a capacitor.
I had a look around and couldn’t find any MPPT chargers for them. I have two questions;
Is the libre-solar firmware suitable for managing this chemistry?
What is the lowest power/cheapest microcontroller that the libre-solar firmware can run on?
I haven’t used the firmware with titanate cells, yet. However, all parameters of the charging algorithm are fully customizable. You could either just add some default parameters for titanate cells here or use the custom type.
The cheapest and lowest-power microcontroller is probably the STM32L073. Thanks to Zephyr RTOS it should not be very difficult to port it to other STM32 microcontrollers, though.
Thanks, that still looks like a $7.8 component
Might a $4.7 GD32F103CBT6 be viable?
Some reports it’s compatible with SMT32F103 (excuse multiple posts I’m only allowed one link per post)
I’ve recently discovered this LTO project it won’t be open hardware, but maybe that’s my best option for now