Battery_chargers

[Bruce S]

Battery Warnings





I hope this picture upload works.

This is a picture of what can happen if the wrong type of charger is used on batteries.

We where testing different types of ways to charge the NiCds, since I can't find one that will handle the voltage size and current size for an acceptable price.

Anyway, forgot to make sure the thermal cutoff was connected and here's what happened.

We have all the safety stuff needed to do tests, but even the safest can have a bad day.

To all those I'm shipping these batteries out to PLEASE safe!

Admin: Sorry if the picture is so big.

Bruce S

[cdg378]

Yep, they do get hot!!

I have been buying closeout malibu solar garden lights from china and taking the parts for experiments, they are very promising as to what can be done with them.

The parts in 1 of these things would cost 30 dollars or more if bought seperately and you can get them for about 5 - 7.00 on ebay, we buy them very cheap from china.

Around here they sell them at the grocery store for 6.99 ;0)

They have a 4.4 V cell @ 80mA, 2 550 mA nicd's and a 100 mcd 4 pin white led.

nicd's are very cool for lighting, I use them on my boat, by pasting a few of these cells in the top of the windows I have virtualy free night and pathway lighting that doesn't draw from the house bank.

10 AA's (5 banks of 2 each), 10 led's and 5 cells is a good starting point, fun stuff.

[libra]

I use 10 mh cells in  a  pack, plus a 7ah gel cell for my radios and find that I can recharge them with a 600ma solar panel or a 800 ma wall wart as long as I watch the charging voltage. It takes about 15-20 minutes to recharge them and the batteries don't even get warm. When the voltage reached 14 volts I simply unplug the charging source. While you can't walk away it does make life simple and I don't have to carry a charger with my radio pack.

Libra

[Bruce S]

cdg;

   Go one better. Go to a Goodwill store or resale shop. I've been finding them there for $5/ set of 4. I'm lineing my front walk way with 'em. I alternate the colors from the whites to amber and then have them start low and then up to the level of the hand rail.

We had a REAL BAD storm come through St. Louis, it took out a 150 yr old tree along with the power. Then everyone got to really see how well and pretty these looked/worked. these were the only way people could see the road. Should'a taken pics , but we were busy getting the tree off the cars.

I'm looking at the next sets to begin linking the cells together for a larger voltage. and can't beat the prices.

I do change out the AA NiCds to the higher rated 700mA ones to take advantage of the longer solar times.

I'd like to dcome up with a better way to control the charging for the NiCds, but you can see from the picture that it needs to be human proof.

Fun stuff that saves me money is great!!

Cheers!!

[cdg378]

I got to tell you that because of my boat I have really experimented with nicd's and led's for light and it is alot of fun and bang for your buck playing with this stuff, my dog has a very cool nightlight from all this too!! Next I'm gonna get him on the treadmill and hang a t-bone in front of him..just kidding.

Look for old power tool batteries with the thermistor cutoff switch in them, there are alot of great circuits out on the web that use these as temperature cutoffs.

Also many great circuits that monitor voltage, when the voltage drops they quit the charge.

For alot of lighting applications big systems and conventional bulbs are a huge waste.

I like the solar cells they put in these lights because they are encapsulated weather proof cells, I am laminating them in styrofoam and epoxy and making nice solar sheets of cells..very cool and promising..you can buy the cells fairly reasonable at some sites aound the net, take into consideration that you won't need glass and tedious soldering to hook these things together and they are a bargain for some applications for a few bucks a cell.

[Bruce S]

Hey can you send a pic of the dog's night light? I would like to see that.

Our APA dog (Sandi) has the biggest problem with sleeping in the dark, I know strange but true.

I like the idea of the thermistor cutoff switch, our professional analyzer unit has one but it must be attached to work, I'll do a google and see what other circuits are out there.

Cheers

[ghurd]

Hi Bruce!

Would this be what you are looking for?

http://www.goldmine-elec-products.com/prodinfo.asp?number=G14366&variation=&aitem=11&mit
em=25

They are smaller in real life than they sound.

Don't look like they will take too many amps.

G-

[Bruce S]

hey G-;

   Thanks for the link. Lots of other nice stuff too.

I may purchase a few to see what the link-ability can be. the price is much better than trying to replace NiCds.

Wonder what the open switch temp is, I've been looking for a thermistor that will trun on a fan at a certain temp range.

Bruce S

[cdg378]

Some of the plans I've seen say they are able to log the current ambient temperature and notice any increase in it...

In other words if your banks temp is 75 degrees at the start of charging, the switch can cut off the charger when it senses a rise in that temperature. Same thing if it's 30 degrees, it just senses the increase in temp.

I really think I'm going for the circuit that monitors voltage rise and when it starts dropping it shuts the charge off, some of these circuits use the temp switch too as a fail safe backup.

About the dog lite, when I leave for the night and won't be back until after dark is when I use the light, he sleeps in the dark OK but I don't want him sitting around alone in the dark when I'm not home and burning a 40 or 60 watt bulb should be against the law for that reason :-)

I stuck a few cells to the basement window where they can't be seen then wired up through the floor and wall to where I want the light..works great. Think about doing more with it too, like under kitchen cabinets and behind some crown molding in one bathroom that has no window.

It's been alot of fun messing with this, and it hasn't taken a huge investment to get excellent results either.

[ghurd]

Those VW PVs have a built in regulator at 13.7~13.8V, and 42 cells for use behind another layer of glass.  Kind of cheap on ebay, but the VW dealer may just give you 1 or 2.  

Mine puts out over 220ma under good sun outside, but rated at 175ma.

I plan on using one for 9 Nicd's with a series diode or 2 to get the finial voltage down a tad.  Should be great for an automatic LED light, etc.  My plan is for an almost pocket sized stereo / MP3 (it works well!)

Just a thought.

G-

[ghurd]

Some VW PVs are NOT self regulated.

Some are, like this one.

G-