I am currently working on a Solar powered project but I am having a hard time making it work:
I have a PCB with an Arduino and a sensor, this circuit consumes 250mA for around 2 seconds every 10 minutes and the remaining time consumes less than 1 mA, I am using a simple BJT TIP31 switch to turn off the sensor and sleeping the arduino to achieve this.
For powering this circuit I am using a 6300mAh 4.2V Li-Ion Battery connected to a TP4056 breakout board set to 1000mA and to a 1W 6V Solar cell for charging the battery.
The goal is to keep the battery going infinitely (or at least give it a good lifetime ~a year maybe) by charging it with the Sun
The battery goes in parallel to a AMS1117 regulator and then to the arduino PCB.
Usually the system works for a couple of days at most (never seen more than 5) and dies.
I am sure I am missing something on this design. My bets are the solar cell is not enough at all but also there are whole circuits that run on a single coin battery for a long time (years) and have a higher power consumption than this one. How can they achieve this?
What do you think it's wrong with this system?
Any pointer in the right direction would be extremely useful. (Papers, previous similar work, researches, maybe changing some components… you name it)
On the top of my head some suggestions I’ve been considering are:
More power in Solar cell (Not ideal because of the size)
Changing the regulator
Maybe changing the battery design to two cells in series to provide more power
Changing to a “smart” charger. I’ve got this at hand but it says it is for LiPO so I am not sure if this will work with Li Ion
Thanks in advance.