battery help, please.

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cat

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Hello everyone,

I just have a question for you all. I’m in the market for a good battery again. Lately I’ve been doing a good amount of clustered launches. I had a rather large lawn-mower battery but I had to return it to its owner. Although I may just go get another (smaller motercycle) lead-acid battery, I thought I’d take some suggestions form you all before I do.

Definitely would *like* to have:
Rechargeable
100+ cold crank amps
Spill or dangerous free
Ability to keep the battery in my living space safely.

I use to worry a little bit about my borrowed lead-acid battery as the warnings on it listed emits poisonous and explosive fumes.

Any suggestions would be VERY helpful! I would love to hear what you’re using in your setup!
 

teflonrocketry1

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I use Gel-Cell or sealed lead acid batteries like this:

https://www.allelectronics.com/cgi-bin/category.cgi?category=160400&item=GC-217&type=store

in UPS units for laboratory equipment. I usually buy ten at a time to replace the ones in a battery pack. The old ones that still work are what I use to launch with.

Look under Batteries at:

https://www.allelectronics.com

then select Gel-Cell (Sealed Lead Acid) for a list of different sizes.
They shipped 10 of these large heavy batteries to us for only $6.00!

Bruce S. Levison, NAR #69055 Section #535 Tri City Ski Busters
 

sveinbjorn

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Originally posted by cat

I use to worry a little bit about my borrowed lead-acid battery as the warnings on it listed emits poisonous and explosive fumes.

How about a wally world cheapie? $35 will do it all day strong.

Lead-acid batteries do put off those fumes, mainly during charging. If you have a porch or other outdoor location to charge it, you should be able to store it indoors. (Just don't spill acid on the carpet.)
If you have a car, you may wish to consider just clamping on to your car battery. Unless you have some hippo-magazoid current requirements, you should do fine..

HIH,
Ed
 

n3tjm

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Lead Acid Batteries are great... but be careful with them. If they tip over, they will leak. That is one reason why I left early from the last launch... I went home... and dumped baking soda on the carpet in my trunk :(. Took a while to take care of that mess :(.
 

bcdlr

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shreadvector

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For our club, we use a car battery in a milk crate to prevent tipping/spilling, but it lives in a garage.

When I go to the desert to launch, I use my car battery and just connect to it with battery clips.

I also use an Estes Command Control launch controller with 2 NiCad battery packs (7.2 V x 2 = 14.4V)

Originally posted by cat
Hello everyone,

I just have a question for you all. I’m in the market for a good battery again. Lately I’ve been doing a good amount of clustered launches. I had a rather large lawn-mower battery but I had to return it to its owner. Although I may just go get another (smaller motercycle) lead-acid battery, I thought I’d take some suggestions form you all before I do.

Definitely would *like* to have:
Rechargeable
100+ cold crank amps
Spill or dangerous free
Ability to keep the battery in my living space safely.

I use to worry a little bit about my borrowed lead-acid battery as the warnings on it listed emits poisonous and explosive fumes.

Any suggestions would be VERY helpful! I would love to hear what you’re using in your setup!
 

Zack Lau

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I've tried all sorts of batteries for powering portable ham gear and what works best for me are 8AH Hawker (Gates) Cyclons.

You can drop them on a rock and split them open and they still won't leak.

They are spiral wound like NiCds so you can get a tremendous amount of current--200 amps out of a D sized cell.

https://www.dmstech.co.uk/cyclon.htm
Spec sheet
 

cat

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Originally posted by teflonrocketry1
I use Gel-Cell or sealed lead acid batteries


I'm very interested in getting a gel-cell can the be crarged with any standard 12volt car battery charger?
 

stevecarr

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You can use a 12 car battery charger.
Be sure that it is a trickle type!
A constant charge or stupid charger will cause them to boil and rupture.
 

cat

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Well i did it! I stumbled upon (ok i searched out) as 12v 18ah Gel-cell. this should be
more then i'll ever need, and thats a good thing. i may do some testing
tonight if its charged by then. acording to there site i can get almost
30min at 30amps (i cant imagion i'll ever been in the field that long)


https://www.thomasregister.com/Cata...&search_string=Batteries&sort=0&narrow_states
=&narrow_text=&pn=03540705&rc=0&sid=0408251410210500042651LW1&uuid=TRGuest
 

rocketdad0934

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first I plug right into the trailer plug on the back of my truck and then work with the cord with a house plug so I caan use a extention cord to get where I want/need. second if you get a jumper pack that has enough amprage to start a diesel in the NE winter it has a handle for carying and I have dropped mine off the front of more than one car so it proves to be rather durable it is rechargeable and if your car doesn't start it will come in handy there also:D
 

bobkrech

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Several words of wisdom on lead acid batteries.

1.) You want to use sealed gell cells for lauchers, not the standard motorcycle or car batteries that use liquid sulfuric acid. Unsealed automotive batteries will leak acid all over the place if they are tipped over whereas a gell cell will not leak if tipped over.

2.) Lead acid batteries are heavy, and battery capacity is directly proportional to weight. For example, a 12V 7AH battery weights 6 pounds, and a 17 AH battery weight ~15 pounds! Shipping the smaller battery by UPS ground will cost $6 or more each, and the larger on $8 or more. Be sure and look at the total cost of your order including the shipping from any vendor before you complete the purchase. allelectonics charges a flat $6 shipping fee for all orders independent of weight, so if you need switches, leds, cable, clips, relays, etc. in addition to the battery, you can save big time ordering from them.

3.) Don't get a bigger battery than you need. They are heavy to carry. A 12 V 7 AH battery can deliver more than 100 amps into a dead short and will launch hundreds of rockets before it needs to be recharged if that's all it does. (A copperhead ignitor uses about 0.005 AH of capacity, you can do the math.) You are unlikely to use more than 10% of it's capacity on a typical day unless you're powering a PA with the launch battery (Be smart and use a separate battery for that). If you take care of the battery, and don't launch more than 100 rockets in a day before recharging it, the battery should last at least 5 years if the storage temperature is below 80 F.

4.) Don't overcharge it. Heat kills batteries. Almost everyone has an auto battery charger. Just set it on the trickle charge mode and recharge it for a couple of days then disconnect it. (Trickle chargers will limit the current to a few ten's of milleamps when the battery is fully charged so the battery doesn't overheat. You don't want to leave a battery charging at more than 0.005 C for long periods of time. For a 7 AH battery, that's 7x0.005 or only 35 ma, and even that's 1 AH in 28 hours, so don't over do it.)

5.) If you're out in the field on a weekend or you can't absolutely can't afford a charger, you can use a set of jumper cables and your car battery to recharge a lead acid gell cell that is not fully discharged or defective. You don't even have to run the motor. Just hook it up for a few hours and you should be fully charged. If the car is not running, you cannot over charge a good gell cell. A few words of caution: Only use this method if you have a good fully charged car battery, and you have launched less than 100 rockets with your gell cell. Do not use this battery to battery recharging method on a gell cell with a voltage below 11 volts, or an old gell cell or one you suspect has a bad cell or shorted cell. It could overheat the battery and cause the gell cell to explode.

Bob Krech
 
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