Solar Powered Mobile Phone Charger Part 2
1,738 views · Published 26 June 2014 · 10:58 · Indexed 30 October 2026
Channel: GrandadIsAnOldMan · 2014 · Science & Technology
This is part 2 of my attempt at a solar powered mobile phone charger. In truth it is more of a battery backup option rather than a true charger. I have assembled a small solar array from cheap garden lights but as soon as I was ready for a real test the sun has disappeared so there will now have to be a Part 3 when the good weather returns. I think this is an interesting project although I do not think this is the best option. However now that I have started this I will finish it so people can see what I have done even if it is not very good. I see plenty more related videos are appearing on the right of my screen now so you should have plenty of others to watch. One big problem with this set up is there is no protection for over charging. ===================================================================== Deslomeslager added this comment to part 1 and I am pasting it here as it gives some great detail on what to expect. I happen to have an htc battery, it says 3.7 V, 1450 mA. I think your older phone might have a less strong battery but I expect it to be 1 Amp (1000 mA) at least. The NiMh batteries are 1.4 Volts, and the LiIon needs up to 4.1 or even 4.2 to be filled 100%. But as the NiMh drains, the voltage slowly goes down, and the charging will be less and less. If the AAA batteries are 750mA the LiIon should be able to charge up to 50% (but you would need to leave the phone off to reach that). Those small panels you have there? Of course, I have those as well. Most of the time they deliver round 2 volts (I measured 2.3 in the bright sun), and 40 mA when shortcut over a 1 ohm resistor. The panel is 2.4cm squared (almost an inch). I tested 8 of them, 2 were not working so I disposed them. And one of them gave 29 mA, but all others gave 40 to 44 mA over a 1 ohm resistor. You need one panel per battery, as the panels are actually 100's of millivolts over what is needed as the sun is not always as bright, and we need to charge as well if it is cloudy. So. Suppose you attach 1 panel to 1 AAA battery (better in parallel, one cell per battery) and if you have 10 hours of sun then the AAA battery might receive 400 mA. The AAA batteries are probably 750 mA or perhaps 1000 mA, so they charge fully in 2 days. Unless you buy one more set of solar garden lights. Now you can have (2 parallel) 80 mA and charge the AAA in one day (if you have 10 hours of sun, partly full and partly just daylight). ===================================================================== I will add this video to my Solar Power playlist https://www.youtube.com/playlist?list=PLA5a2xPRSrB1SVLRn_D16dRvTrocMhFPq I have also created a playlist Solar Powered Mobile Phone Charger project to keep this series of videos together https://www.youtube.com/playlist?list=PLA5a2xPRSrB3fP_vVXEz2y88dkDR2_gPl I have thousands of videos on YouTube covering a wide range of subjects. To find them follow my search guides https://youtu.be/ceBSOoOHcgw or https://youtu.be/Zj4UgwkwYRk or see my playlists page https://www.youtube.com/user/GrandadIsAnOldMan/playlists?flow=grid&view=1 Generally my projects are for my grandchildren to enjoy. OK, I enjoy them too. If anybody else likes them, that is a bonus. I like to keep my work as simple and basic as possible so that it can be copied easily and improved by anybody who wants to try themselves. I recycle or repurpose items rather than buy new and when I do buy I like to keep it cheap. https://www.youtube.com/user/GrandadIsAnOldMan
