Household solar 12V device charger

Picture of Household solar 12V device charger
This in house 12v charge station is a simple solution for charging of phones and other small devices in the event of power failure.  It is derived from many similar projects here.  I used 3 12v batteries found in a used electric scooter.  They may not be the best configuration, but wired in parallel they maintain a constant charge of around 12.2v.  They are topped off by the Amazon solar panel and controller here:

I place the batteries and controller in the basement close to the window which the panel is mounted under. The output from the controller then leads up to a standard wall outlet that has been modified to accept a standard 12V plug.  It is located in the kitchen. This then can be used with any sort of adapter to power or charge small devices independent of the main electric system.
Macattacku11 months ago
Ok. 13.2 volts is fine then. Its just a well researched and established fact then when a lead battery isnt fully charged it degrades. The worst thing u can do to a lead battery partially charged for months. Its internal resistance gos up and capacity gos down.
bonedoggie (author)  Macattacku11 months ago
The solar panel always tops it off. I'm not sure you paid attention to my instructable. BTW, it is spelled "goes".

Macattacku11 months ago
Dude. Those batteries are gonna die. 12.2 volts is not a healthy charge. They are gonna sulfate and degrade and after a few months they will barely work. A 12 volt lead battery needs to be fully charged to stay good. Fully charged is 12.6-12.7 volts. Empty is 11.8. Its only half full. That is bad for the battery. It should be charged by a source that can provide at least 13.2 volts 13.8 or 14.4 is preferable. A cig lighter will not work. This thing will fail on u during a real power outage.
bonedoggie (author)  Macattacku11 months ago
Thanks, I reckon. I just checked the output and it's 13.2V. This has actually been live for three months and there has been no degradation. The charge is applied through the voltage regulator from the solar panel. When I installed it the batteries were only at 11V. They have been topped off since a week after install and have not dropped. I charge my iPhone every day no prob. I found the batteries in a discarded electric minibike and they have seemingly worked fine. If the power drops, I'll just drop a new deep cycle in their place. So, FWIW your comments have not been proven out by time. JB

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