Looking for a medium current cheap battery pack

[airman00]

Hi,
I've been looking for a relatively lightweight and cheap battery pack for my robot but I can't really find what I need.

Specs I need: between 12 and 24 volt(including 12 and 24) ,  between 15-20aH, must weigh 10lbs or less , and must cost less than 100 bucks . All these are approximate values, a little more or a little less won't hurt.

I'm not asking you to go out searching for me , but if you stumble across on some surplus lead acid or NiMH battery, please post a link to it .

Thank you

[Admin]

Motorcycle batteries?

tried EBay?

[airman00]

Motorcycle batteries?
tried EBay?

Motorcycle Batteries weigh too much . 20amp battery weighs 15 lbs.

What do you think about this: http://cgi.ebay.com/Lipo-Battery-11-1v-1000mah-20C-20-amp-Lithium-Polymer_W0QQitemZ220280339139QQcmdZViewItem?_trksid=p3286.m20.l1116#ebayphotohosting

It claims to have the following but on top it says 1000mAH .Then later in the description it says maximum charging is 1000mAH.

Lipo Specifications:
Dimensions: 2.7 x 1.4 x 0.85 inches
Weight: 3.5 ounces (99 grams)
Output: 20 amps continuous, 25 amp burst

[Admin]

Hmmmm but its not within your required voltage or Ah specs . . .

My helicopter uses a 900mAh battery and lasts about 11 minutes continuous flying. Scroll down to see the battery specs on it.

Check this page:
http://www.all-battery.com/148vli-polymerandli-ionbatterypacks.aspx

Fits your specs and then some:
http://www.all-battery.com/148volt-3000mah15cli-polylipo4cellbatterypack.aspx

But you may need to buy a charger to use these guys . . .

[airman00]

oops sorry if I was unclear  , I just brought up that on the side. It wasn't really related to my search for a lightweight 15-20aH battery for wheelchair motors .

[Razor Concepts]

Never buy ebay lipo batteries. 95% of the time they will puff up and die.

I would go to www.hobbycity.com and check out their Zippy line of lipos. They have 3s 5000mah lipos for the best prices, wire two in series and you get 10ah at 12v, at a lot lower weight than other types. They also sell chargers for ~$60

People have mixed opinions on the tenergys... lots of people have had their tenergy nimh batteries fail.

[jamort]

wow i can give and interesting suggestion....
I have a Ryobi drill I purchased from home depot for about 50$ and it has a 12v battery and I belive you can get 24v but there rechargible and power great um i belivbe there lithium ion i would have to double check... and if you go  the drill you could take out the place were you connect which is a thing htat connects then theres a positive and negaticve charge and there you go you got yourself a battery...

[SciTech02]

wow i can give and interesting suggestion....
I have a Ryobi drill I purchased from home depot for about 50$ and it has a 12v battery and I belive you can get 24v but there rechargible and power great um i belivbe there lithium ion i would have to double check... and if you go  the drill you could take out the place were you connect which is a thing htat connects then theres a positive and negaticve charge and there you go you got yourself a battery...

Darn man, I have the exact same Ryobi 12 volt battery for my robot!  I got just the battery and charger at a swap meat (flea market) and it seems to work fine.  I believe they're NiCd batteries (most power tools use that type of battery).

As for airman00's battery, you could connect 2 smaller batteries in series or parallel and get a larger battery.  You could then charge it at its total voltage, as if it was a single battery.

[Xone G0D]

 As far as cheap and selection is concerned:  Pack your Multimeter some leads and a few bucks.  Go to your local Metal recycle yards, scrap metal yard or what ever you may call it.  Normally they will buy used car, motorcycle, ATV, and many other types of batteries for about 2 bucks and they will sell them to you back for four.  Thats How I get most of my batts. Don't think that all of them are junkers, sometimes warranties or service plans force companies to dispose of used batteries in this manner and show receipts from a scrapyard to avoid Gov taxes.  I have gotten Several 12v gels for four bucks... I hate to share this secret... but hell, you give and you take to give again....

  It does give you some selection and at the very least lets you see some other options... Not to mention, it will make some wiggle room in that budget of yours... lol....


..X..