On Sat, 15 Jul 2017 18:12:14 -0700, Jeff Liebermann
wrote:

On Sat, 15 Jul 2017 15:15:03 -0400, wrote:

When I opened it, I was shocked. Instead of AA or AAA batteries, I found
two square "pouches". Sort of like tin foil covered bags that are
labeled as batteries.

Those are LiPo (lithium polymer) batteries, normally used in cell
phones and quadcopters. Photos:
https://www.google.com/search?q=lithium+polymer+batteries&tbm=isch

Yep, that's what they look like. I have never seen these before now...

Besides those weird batteries, I found a small circuit board with 6 or 7
very small IC chips.

That's the charge controller.

Heck, I need a magnifying glass just to see
the solder joints on this thing.

You'll also need specialized tools to build and repair those, such as
a hot air desoldering station, reflow oven, solder paste, and various
chip manipulation tools.

Yep, I'm sure they sell all this stuff, but I'm not investing the money
in it. I'd probably spend several hundred dollars to get all this stuff,
then spend a thousand dollars to my eye doctor for eye strain, trying to
see these parts. Then I'd remove parts, which are not labeled, and after
wasting hours trying to understand it, I'd still end up tossing it in
the trash. I think I spent around $25 for this charger, and dont think I
got my money's worth out of it, but I am fully aware it is not meant to
be repaired. Like most stuff these days, it's disposible.

I'm not even considering repairing it, I just want to salvage the solar
cell and make use of it.

I should also mention that last winter Walmart had some portable
cellphone chargers that are meant to be used when the phone's battery
dies. You charge these power packs by connecting them to any phone
charger or USB port. These battery packs sold for $6. I bought two of
them. If I plan ot use my phone in a place that has no means to recharge
the phone's internal battery, I just carry these power packs in my
pocket.

I thought the solar charger was better, but since it did not last even a
year. I spent close to $20 to save about 50 cents worth of electricity
to recharge a battery pack.


The plan is to salvage the solar panel, and trash the rest of it. The
solar panel is a lot bigger than the ones on those solar lights, (about
4 x 5 inches). I'm suspecting the solar panel is still good, (I will
have to test it to be sure, by hooking a volt meter to it when it's in
the sun).

You might also want to measure the short circuit current. Just put an
ammeter across the solar cell leads and see what you get.

My question is whether I can connect this solar panel directly to a
rechargable battery,

No.

or do I need some sort of diode or other components
between it, and the battery(s).

Yes, a solar charge controller. What type and size depend on the
ratings of the solar panel and LiPo battery, neither of which are
currently well defined.

So, does this have to be designed by hand with individual components, or
is there a chip available that does it all? -OR- can a ready made board
be purchased that is intended to control solar chargers?

(I know those solar lights have very
minimal components).

They also do a great job of killing batteries. LiPo lasts longer than
most, but few batteries will last very long after being cycled between
full charge and total discharge every day.


I have to disagree about these solar lights killing batteries. I have
several of these lights mounted on my house, and several more on my
workshop shed. I paid from $5 to $10 for them. I attach them with 1/2"
conduit straps to the wall. Some of them have lasted 5 years, others
have died after 2 years. But considering they are charged and drained
365 times each year, and operate off of one NiCd battery, I really cant
complain, about their life expectancy. Every so often a local store
sells replacement batteries in a 4 pack, ON SALE for about $6. So, for
$1.50 per light, I just replace the dead batteries, and get another two
or more years from the lights.

Now, if you buy those solar lights that cost $1, they DO NOT last long.
And I also found that if you stick them in the ground along a sidewalk,
they get broken faster than the batteries die, and if you dont step on
them or chop them up with the lawn mower, they wont survive the snow in
winter. Wall mounted is so much better, and in my case they perform an
inportant task, they light up the stairs by my door, without needing to
operate an AC porch light, which will cost a lot more on the electric
bill.

But it seems to me that there probably needs to be
some sort of component (at least a diode) to protect the battery current
from back-flowing into the solar panel.

True. Schottky diode for minimum voltage drop. It's often inside the
charge controller chip.

So, would one of these diodes be all that I really need to use this
solar panel?


In the end, this will just
become a solar charger for NiCd or NiMh rechargable batteries, or I
might even turn it into a solar light sort of thing.

In the end, if you use it as a solar powered garden light, you'll
likely kill the battery. You need to match the battery, charge
controller, and solar cell to each other. So far, you're not doing
that.

Anyhow, what is needed to attach this solar panel to a common
rechargable AA or AAA battery?

Better numbers.

I guess you mean I need to determine the output of the solar panel. I'll
have to see what I can measure.