Now testing a recovered 18650 cell with a couple of solar panels to charge.
This one should hopefully last longer because the solar panels no longer have a voltage drop with a diode.
Once the lithium charging boards with extra protection arrive (they're taking ages) I'll make a board up with all the bits properly soldered.
I suppose a board like this could be used as a reasonable battery backup type system for plugged in sensors. Saying that, if the power goes it will probably take out the server, wifi etc so it would be a little pointless.
![](https://lh3.googleusercontent.com/WZGm9AKm-TMmO5hfam9LCyHkbVqHurhQALqIJ3kX8TtYujgNL5OPus4pJwtnqYrDisKBvmm6ENKG64COUPWae5aW0BUuWmIo_IelpC01I0Ody6Ysv8vxeG7A6mF_ayTnOw6mdGRRfyD7g8nUG5Eb_n0mT5AhjebMpi2cE-xkYuIoPsVw5MLErjhYtdcKKaraXfd5p9yJ1wVx3Wl_nMLQvSwFE-U6V-pWgnHpdjQOpIK2MyxlpHTEDBziRO-2xhHqSzutBXGtjsKezkEXTnBxvHlmyb2oV9lDBQIWDdDkMdXBUgq33MMgbrzyfnl0LK_vxvkHHM9hbYet2sHST0-y89tSAEsHfj4r8u24W8vCLBuoPTKLQiSfvhz_uXMfqOFSG69xDb5QCauxKvimLKpU2QjnMshMYcaHh7571yc1bISVoS5-siImpBQBIBLYFhc3A1bsNLEKPkdE_MJ0ZX0zAGonVNMOXsdLO05GhB-PBu2oZFeO3YsvVYbaF6DqoSCpBHKBne1g5LVYqhCjng6RCuY4Lqc0QaLTB3M_pD6T_japyG29GjWq_1rV1554on21iDeDFw=w826-h619-no)