What to do with 100 9V batteries? / General Science and Electronics / Forums

Forums

4hv.org :: Forums :: General Science and Electronics

« Previous topic | Next topic »

What to do with 100 9V batteries?

1 2 next

Move Thread

LAN_403

DrZoidberg

Wed Dec 27 2006, 09:47PM

Registered Member #350 Joined: Mon Mar 27 2006, 05:14PM
Location:
Posts: 106

I got a batch of 100 9V zinc carbon batteries very cheaply.
What could I do with them besides killing myself?

If I connect them all together I get a 900V battery that can deliver up to 100mA. Not that much but enough to charge a 1kJ capbank within 10 seconds.

Any other uses? I guess it was probably a waste of money.

Simon

Wed Dec 27 2006, 10:34PM

Registered Member #32 Joined: Sat Feb 04 2006, 08:58AM
Location: Australia
Posts: 549

The biggest problem with this kind of thing is that batteries don't turn off. You'll see what I mean if you try to wire this thing up. Unless you plan things very well, you'll be fiddling with loads of live wires at around a few hundred volts.

Any other uses? Hmm...

ragnar

Wed Dec 27 2006, 10:53PM

Registered Member #63 Joined: Thu Feb 09 2006, 06:18AM
Location:
Posts: 1425

Hmm... giant 'LED throwies'?

Series coloured LEDs, solder them to the batteries permanantly, and plonk a big neodymium magnet on the case. Now throw it onto something metal, out of reach, and it'll look pretty at night... until it goes flat, at which point it'll look like an eyesore.

But that involves the spending of more money for and might be considered environmentally questionable =P

Marko

Wed Dec 27 2006, 11:16PM

Registered Member #89 Joined: Thu Feb 09 2006, 02:40PM
Location: Zadar, Croatia
Posts: 3145

Seriesing them all into a giant 900V battery would definitely not be everyday-seen.

Plugging them all together safely may, although, be tricky.

You could although make something ingenoius, like some way to have two such 'strings' of 50 batteries arranged, in some kind of holders, but all separated and 'turned off' literally.

When you want to use the monster battery you just plug the two strings together.

...

Wed Dec 27 2006, 11:39PM

Registered Member #56 Joined: Thu Feb 09 2006, 05:02AM
Location: Southern Califorina, USA
Posts: 2445

It is always good for pulling nice juicy sparks off of ;)

Also, try hooking it up to a nice fat xenon strobe tube (one out of a ssy-1 laser put under water would be great) to make a really big flashlight.

I tried this once with a smaller U-tube and a smaller bank of batteries, I had the tube partly submerged under water to prevent the electrodes from shorting with the hv wire from a large plasmaglobe supply dipped in as well (it was in a 2" pvc endcap to keep it insulated from ground). Without the batteries connected the tube would glow purple, and with it the tube glowed bright white.

You might consider PWMing it with a 1200v fet to make it variable and save the battery like...

Madgyver

Thu Dec 28 2006, 10:24AM

Registered Member #177 Joined: Wed Feb 15 2006, 02:16PM
Location: Munich, Germany
Posts: 214

balsamplack wrote ...

Hmm... giant 'LED throwies'?

...snip...

But that involves the spending of more money for and might be considered environmentally questionable =P

Yeah, I never realy understood why people make them. Its just a big waste of money and absolutley meaningless.

Tom540

Fri Dec 29 2006, 06:59AM

Banned on 3/17/2009.
Registered Member #487 Joined: Sun Jul 09 2006, 01:22AM
Location:
Posts: 617

You can snap them directly to each other without any wires. Just take the two that are going to be on each end and put a wire on both of them before you connect them and maybe wear some gloves.

Marko

Fri Dec 29 2006, 12:05PM

Registered Member #89 Joined: Thu Feb 09 2006, 02:40PM
Location: Zadar, Croatia
Posts: 3145

Wearing gloves and handling pretty deadly HV *all the time*.

This is what I tried to avoid, if anyone understood what was I saying...

Steve Conner

Fri Dec 29 2006, 12:30PM

Registered Member #30 Joined: Fri Feb 03 2006, 10:52AM
Location: Glasgow, Scotland
Posts: 6706

Yes, you should be able to build the beast in two halves where the batteries aren't actually connected in series until they are put together. Unfortunately, I get the idea that you'd end up spending more on parts to build the connector than you did on the batteries.

Early radio and TV experimenters like John Logie Baird used to use batteries like this. The standard voltage was 90V, but I heard that Baird once built a 1200V battery bank, then used it to accidentally set his lab on fire and nearly electrocute himself.

They are also a neat echo of the old "Voltaic piles" from last century. (oops, two centuries ago now!) Before generators were invented, people like Volta (who gave his name to the voltaic pile, and you guessed it, the volt) would build huge stacks of battery cells to get electricity for their experiments, like making electric arcs and getting frog's legs to twitch. They literally were piles of metal plates and pieces of paper soaked in electrolyte. Some of these piles were pretty big and could power carbon arc lamps. Maybe you could read up on these old experiments and try recreating some of them with a stack of 9v's.

Maybe as a compromise, you could build the battery in 10 90V blocks that you plug together only when needed. That would make your life easier if you decided you wanted 90V @ 1A instead of 900V @ 0.1A one day.

Marko

Fri Dec 29 2006, 01:10PM

Registered Member #89 Joined: Thu Feb 09 2006, 02:40PM
Location: Zadar, Croatia
Posts: 3145

You don't need any special connectors since battery connectors are good enough.

I think just wisely securing them betweenn two sheets of wood would do well.
Hope I don't need to draw what I think.

90V stacks would still, although less, be dangerous.

1 2 next

Moderator(s): Chris Russell, Noelle, Alex, Tesladownunder, Dave Marshall, Dave Billington, Bjørn, Steve Conner, Wolfram, Kizmo, Mads Barnkob