Comments on: Solar Charge Battery Powered Toys

By: admin

admin — Mon, 04 Feb 2013 14:13:07 +0000

In reply to Robert.

Hi Robert,

It could work. A couple of thoughts – make sure the batteries are NiMh. We haven’t done a lot of work with direct charging of AAs, but one rule of thumb is that you don’t need a charge controller between the battery and the panel as long as the panel in Wattage is < 10% of the Battery Capacity in Watt hours. If higher than that, you risk overcharging. A quick guess is that your panel is about 0.5 Watts. If your batteries are 2500mA, 1.2V, than the Watt hours of your batteries should be 6 in total. Second, the Voltage of the panel should probably be in the 3.5-5V range. Check with a multimeter to be sure...finally, yes you would need to have a blocking diode.

By: Robert

Robert — Sat, 02 Feb 2013 14:19:24 +0000

Congratulations on your solar charger and I wondered if you could help me with a small problem.
I have a home weather station. the wind speed gauge is, of course on the roof but runs off 2 AA batteries.they last for about a year but of course are difficult to replace.
I have a small solar panel(about 2×2 inches)which I got from a motorised toy. can I install this with a diode to charge my batteries. I do not know the voltage of the panel or whether this is important.
I live in Cyprus so have no shortage of sun! but equally don’t know anyone here to ask.
Thanking you in advance.
Robert

By: Solar charge battery powered toys… « adafruit industries blog

Solar charge battery powered toys… « adafruit industries blog — Sun, 27 Dec 2009 05:17:46 +0000

[…] Jeff writes in with a quickie solar project… I recently purchased two remote control cars for my nephews from a dollar store. The cars came with three rechargeable AA batteries and also a cheap AC charger that connects to the car, but unfortunately grew hot when plugged in (a classic wall wart). So I’m giving them the cars with a solar panel and withholding the AC chargers. The best part is how easy it was to make it all work as I piggy-backed on the car’s built-in charging circuit. […]