Mastodawn

👾May 5, 2024

#meshtastic #battery #solar Test is now in progress. Leaving T-bat + T-beam #tbeam + solar panel indefinitely at velux roof window to see if it ever runs out of power.
Parts:
2 x 18650 batteries
5 V solar panel 28 cm x 16 cm max 1 A
https://www.botnroll.com/en/solar-panels/3244-monocrystalline-solar-panel-5v-1a.html
https://www.lilygo.cc/products/t-bat
https://www.lilygo.cc/products/t-beam-v1-1-esp32-lora-module
2 x USBA to USBA micro cable
10 m duct tape
coffee for waiting a week

bluetooth device for reading messages off T-beam

Monocrystalline Solar Panel (5V 1A)

botnroll.com

👾May 5, 2024

#meshtastic Test over 1 day shows that #lilygo T-beam with T-bat and solar pannel charges T-beam 18650 3450 mAh battery to 100% when darkness falls. The 18650 3450 mAh battery of the T-bat is of unknown charge but shows 'done' which in my book means full. #tbeam #tbat #solarnode #node #solar #lora Parts list is in another post to the higher post.

👾May 8, 2024

So on a rainy day the tbat seems to have not recharged much and the tbeam was down to 93% by night-time.... but hopefully will last till ☀️ -up and get charged to 100% via tbat... if not.. then....

👾

Over 6 hours at night the T-beam's charge level went down by about 10% points from 93% to 82% (the T-bat is in an unknown charge state)

Now 09:30 CET the sun is shining the T-bat shows it is charging (see pic) but the T-beam plugged into it is at 70% battery when unplugged briefly from T-bat and not sure the T-beam is charging too yet. #meshtastic #tbeam #tbat #lilygo

12:30 CET T-beam at 57% while plugged all the while into T+bat which is charging from panel. Looks like no charging of T-beam is taking place thus far this morning.

22:00 CET T-beam at 20% and not seeming to get any power from the T-bat despite decent sunshine today that should have charged the T-bat. Perhaps not so simple after all..... looks like a no-go......

Am now charging the T-bat battery fully from the mains to see what happens to the T-beam power level if T-bat has a full battery i.e. simulate a full solart charge to see it that is the only problem.

👾May 10, 2024

After a brief, no not full, charge of the T-bat battery from mains and returning it to the T-bat, at 06:00 CET the T-beam is showing 17% and the T-bat has no lights on. (Has green light on when providing usb 5 V power out). At. 06:30 the sun ☀️ is on the panel and the T-bat charge and green light came on, and the T-beam went to the mode showing USB power being used - no batter indicator shown. Question is will the T-beam's battery be charged eventually today if the 🌞 plays along?

👾May 10, 2024

No. After a day of sunshine the T-bat is still charging and not fully charged (no green 'done' light) and the T-beam is empty 3% all the while. The setup Solar Panel -> T-bat -> T-beam does not seem to work. Perhaps when the T-bat stops charging from the sun, then it will charge the T-beam but I fear not. The drain of the T-beam is too great. #meshtastic #tbeam #tbat #SolarNode Is it not logical that same spec batteries cannot charge each other?

👾May 10, 2024

Nope. T-beam not charged at all from T-bat despite good sunshine all day.