Need help assessing potential issues/dangers using the TP4056 in solar nodes. This summer I deployed my first solar node. It uses the following hardware:
- RAK19007+RAK4691
- A noname solar panel from Amazon that provides around 6.8 watt of power at most, unloaded the voltage tops at around 6 volts.
- A TP4056-module
The circuit is constructed as in the figure below.
The reason I didn’t use the solar circuit on the RAK19007 was to prevent damage since the panel voltage is to high. It has worked flawlessly this way during the summer but now winter is coming in Sweden and I’ve taken it down. Next year I want to improve upon the design and both add power metering as well as switching the TP4056 for the more efficient TP5100.
Researching the possible upgrades I sprung across r/Gameboy at Reddit and this post: Reddit - Dive into anything.
It seems like using the node this way may damage the battery since the low draw of the node itself may cause trickle charge of the lithium battery (not good). Have I understood this correctly and if so how can I improve and make my design safe?