Society of Robots - Robot Forum

Electronics => Electronics => Topic started by: dellagd on May 02, 2009, 05:37:42 AM

Title: SoR Project - solar battery charger
Post by: dellagd on May 02, 2009, 05:37:42 AM
me and TeslaHV9 are working on a solar battery charger that can charge 3 AA (outputs 5 volts for 3.6 volt batterys) at once at .15 amps in direct sunlight. I was woundering if we would be using AA or like special battery packs.
Title: Re: SoR Project - solar battery charger
Post by: SmAsH on May 02, 2009, 05:40:40 AM
wait, so what is your question? do you want to know if you can charge packs?
Title: Re: SoR Project - solar battery charger
Post by: dellagd on May 02, 2009, 06:45:10 AM
i wanted you guys's oppinion and If this will work with the batteries we will be using on the OSCAR
Title: Re: SoR Project - solar battery charger
Post by: hazzer123 on May 02, 2009, 06:59:53 AM
I don't think we will be restricting our users to a certain battery pack, so you guys are just creating an option for them :)

So the idea is, you choose whichever you think is the best, but try to take into account these things -

Price - try to keep it low cost
Availability - use things found easily all over the world, or give information about alternative components which are sold in other parts of the world
Danger - include warnings... if you are using Lithium batteries especially!
Design - try to make your module noob-proof. Use connectors that can't be inserted the wrong way, or design them so that incorrect connection doesn't do any harm.
Flexibility - Make your module flexible... Could they use a 6V battery? If not... do we need to design another module for this?
Title: Re: SoR Project - solar battery charger
Post by: SmAsH on May 02, 2009, 07:22:02 AM
ultimately you want this to be very flexible and make it stand out from the rest of the competition. what will make yours any better than the current made in china $5 a piece crap?
Title: Re: SoR Project - solar battery charger
Post by: Razor Concepts on May 02, 2009, 11:08:53 AM
You can make a decent charger with a solar panel and a diode, that would be the simplest way.
Title: Re: SoR Project - solar battery charger
Post by: dellagd on May 02, 2009, 12:07:32 PM
I'm not sure if it would be better, but it is made from 4 solar cells and I used the from those solar path lights. I was wondering if this setup would work with the batteries we are using for oscar.plus do I really NEED a diode?
Title: Re: SoR Project - solar battery charger
Post by: Razor Concepts on May 02, 2009, 12:31:00 PM
If you dont have a diode, at dark times your batteries will try to charge the solar panels  :-\
Title: Re: SoR Project - solar battery charger
Post by: dellagd on May 02, 2009, 12:55:38 PM
woah, how would that work  ???
Title: Re: SoR Project - solar battery charger
Post by: Razor Concepts on May 02, 2009, 01:08:51 PM
It wouldn't. That's why you need a diode  ;)
Title: Re: SoR Project - solar battery charger
Post by: SmAsH on May 02, 2009, 04:04:07 PM
the diode will let the current run from one way only as you know. this means after it has charged it will not let itself discharge into the solar panel.
Title: Re: SoR Project - solar battery charger
Post by: dellagd on May 02, 2009, 04:47:01 PM
the diode will let the current run from one way only as you know. this means after it has charged it will not let itself discharge into the solar panel.
I see what you mean.
I just don't see how it can possibly discharge into a panel  :-\
Title: Re: SoR Project - solar battery charger
Post by: SmAsH on May 02, 2009, 05:21:44 PM
i cant think of an easy way to explain this..... just make sure you put diodes in, ok?
Title: Re: SoR Project - solar battery charger
Post by: dellagd on May 02, 2009, 06:23:07 PM
I believe you  :)
I just don't get it.
I will add diodes and then add a member tutorial on how to how it
Title: Re: SoR Project - solar battery charger
Post by: Razor Concepts on May 02, 2009, 07:35:45 PM
Er you only need one diode across the positive line. That's it, probably doesn't deserve a tutorial.
Title: Re: SoR Project - solar battery charger
Post by: SmAsH on May 02, 2009, 07:39:57 PM
if it had a tutorial it would probably be too short anyways... isn't it pretty much just a panel, a diode and maybe an led? with the I2C of coarse...
Title: Re: SoR Project - solar battery charger
Post by: dellagd on May 02, 2009, 08:50:18 PM
no it wouldn't be a mod, it would just attach itself to the power mod and charge its battery. I will make a diagram and post it on my webpage dellarobotics.weebly.com
Title: Re: SoR Project - solar battery charger
Post by: dellagd on May 02, 2009, 09:03:59 PM
or I could make a regular $50 board, hook up a transister to it, and then run the battry charging power through the transister, so the master could actually send a signal to "begin charging batteries". I think that would be pretty cool.
Title: Re: SoR Project - solar battery charger
Post by: SmAsH on May 02, 2009, 09:42:09 PM
it would be alright but not entirely necessary...
are we actually having a power module?
i mean... wont the master have its power regulation ob its board?
like the axon and $50 board do...
what you can do to improve on this idea is have a circuit that senses the battery voltage and turns off when its full..
there are many ic's out there that can do this for you..
for the idea with the transistor:
i think it would add too much complexity to the idea of a charger...
because then you would have to have yet another chip on there to co-ordinate the I2C.
just my thoughts...
Title: Re: SoR Project - solar battery charger
Post by: dellagd on May 03, 2009, 06:36:16 AM
ok