Axiom7

I am thinking of replacing the gel cell battery in my field box with a life or lipo battery. I am wondering if either battery type would work. I would like to make sure that it will run a glow clip and a starter at the same time if need be. I usually use a hot shot glow starter, but in the times that I need a corded glow clip, I would want to make sure it would run both. I have a sullivan 12v starter. I have been out of the hobby for about 15 years and I have very little knowledge of the newer battery tech.

kenh3497

It sounds like you neither battery on had so one will need to be purchased. IMO the LiFe is the preferred battery to use. It (LiFe) is less fussy about state of charge and stores better. Both chemistries are fussy about over discharge but the LiFe may be a bit more robust than the LiPo in that respect. It you are handy then there are on line stores where you can purchase individual cells and build your own pack. Both chemistries need to be balanced charged so no difference there. A charger that will charge and balance the respective chemistries is needed. "Any old" charger will not work as both need to be charged to a specific voltage and over charging can be a disaster especially with LiPo.

I'm switching over to LiFe for all my flight packs as the old NiCad and NiMh packs reach the end of their life. I also plan on a LiFe for my starter this winter.

Ken

Axiom7

I really want to cut down on weight. I do not have either type battery right now. I am getting in a rx life battery. But I still dont know if a life battery would handle it.

scale only 4 me

My Feedback: (158)

I haven't used a field box / power panel since I raced Quikies in the early 90's, Glow drivers can be charged quickly with a field charger

This is how I run my stater, 3s Lipo works great

Axiom7

I am wondering if I can connect 2 6.6v life packs together to make a 13.2v life pack. I really don't like the thought of the volatility of the lipo packs.

jester_s1

There's nothing to worry about with Lipo batteries regarding safety. Yes, if you short them out, puncture them, or overcharge or overheat them to the point that they swell up and burst they will burn.So don't do those things. They are perfectly safe as long as they are handled properly. The go to setup these days is a 4 cell lipo somewhere between 2000-3000 mah mounted onto the starter itself. It's light and convenient, and has enough power on a typical 12v starter to get anything up to around 20cc going. I find cords to be a significant safety hazzard as do many others, so the power panel has got to go. Use a rechargeable glow driver and a self-contained starter/battery and call it good. If you want to use an electric fuel pump, it's easy enough to wire a connector for it to run off of your starter battery too. Since you're buying everything new, I'll also suggest the twist on type glow driver as opposed to the ones with the finger type attachment. The twist on ones are more durable and won't get loose and fall off at the worst possible time.

bigbri

My Feedback: (287)

I had a lipo cook off on me! Was spectacular! So much so, the ones I have left are stored in nomex bags inside a 20mm steel ammo case. My field box is powered by a 4 cell a-123 battery. Works great! And safe! Starter, glow plug igniter ect! Radical Rc will make one up for you!

Axiom7

how many volts is your a123battery and how many milliamperes? I really just want to cut down on weight, but I do not want to limit the lighter battery to just the starter.

Gray Beard

My Feedback: (-1)

I still have a field box but it is used for tools and other big items I don't want all over the floor of the van. I use the 18 volt NIMH pack I bought for a couple bucks with a charger from Harbor Freight to run my starter.Same set up as scale is showing you. Only thing I use a Lipo on is my small electric plane and those packs are stored in double FP bags at all times. LIFE are a bunch safer. I just saw a lipo cook off while the plane was in the air.
I have no battery at all in my field box. When my electric fuel pump finally gave up the ghost that was the end of ever using the power panel too. Just a glow stick and starter are needed now days.

ltc

My Feedback: (3)

If weight is your concern, then it is LiPo
If you don't want to worry about charging and/or storage charge, then A123 chemistry.
just the nature of the 2 battery chemistries.

OliverJacob

My Feedback: (12)

Lipos deliver more current then most Life cells. But Lipo fires do happen without any obvious cause. This happens mostly when charged or shortly after. You should put them in a safe place a steel ammo box of an old safe would be good.
Life is safer to use, but you'd need a battery with enough capacity do deliver the current.

Another thing to consider is the amount of charge / discharge cycles the battery will last.
I use a lead acid lawn mower battery and have a huge rolling tool box to store it. This last a few years and has enough
capacity to charge my Lipos at the field and start my engines.

Gray Beard

My Feedback: (-1)

An 18 volt battery and this old starter works on the DLE 30. The cheap quick charger charges the pack up in three hours. The LIFE is still lighter though

ltc

My Feedback: (3)

Perhaps this is useful
" http://www.rcgroups.com/forums/showthread.php?t=1139699 "
if the link doesn't come they, go to RCG and look for thread 1139699 from Julez

600Bob

You can buy LiFe batteries to replace Pb in motorcycles but not LiPo. So LiFe or A123 is closer to what you are looking for.

scale only 4 me

My Feedback: (158)

The cost of Lipo or LiFe over Lead seems like a risky expense to save a couple pounds in a flight box

Hydro Junkie

The biggest thing to consider isn't the voltage. Most look at voltage as the be all/end all to every problem. I'd be looking at amperage ratings as well. Run a few packs in parallel and you should be good to go. It wouldn't take much to make a harness to connect two or three packs together and to the power panel.

Axiom7

Thanks for all te replies. I just went to Batteries plus and got a 12v 7ah sla battery. Heavy, but I just thought to myself, stop being a *****!

OldScaleGuy

My Feedback: (2)

I replaced my 12v gell cell with an 850mah 3S lipo. Much lighter and low cost, it was around $10. Rarely needs to be charged. Works great and as i get older, weight becomes more of an issue.

jester_s1

It's not about the weight of your field box. It's about having a starter that is easy to handle and use. How do most accidents happen at the flying field? Most start with the pilot getting frustrated or distracted. A lightweight starter without a cord is easy to manage with one hand and is also easy to put away without having to look at what you are doing. Ditto for the battery type glow drivers instead of the corded ones. I'm a huge fan of lipo batteries for starters since they keep the weight and bulk down and deliver plenty of power. The safety precautions for handling them are fairly simple, so there's no reason not to go that route if you already have a lipo capable charger.

OldScaleGuy

My Feedback: (2)

For me, the weight of my field box is important.

aspeed

Weight is an issue for me as well. I am not really old, well, fairly, but going up the steps and out to the car is a struggle on a hot day. I am using a 5 ah SL Acid battery, and it just does not put out the amps to start even a .40 when it is a bit low. I think I may go to four A123 type 2300 mah, not for total capacity, but because it takes the high drain. It would be nice to have a separate battery for the starter and do away with the cord, but that is more maintenance, and weight too. I really like the meter on the field box to know the plug condition. I was very tired of cranking with a blown glow plug. Those little sub C cell 1.2 volt starters really P me off, and I never use them any more, even though they are handy. I doubt that I will go to LiPo though because of the fire hazard, unless I just have one around to use up.

scale only 4 me

My Feedback: (158)

An easy way to lighten up that field box, remove starter motor, remove glow cord or glow driver, remove windex bottle, remove paper towels,, Go Gas.

p.s.
Aspeed, if that 5amp battery can't start your .40, it's dead or your starter is bad,,, something needs replacing,
The 3s 1800 I posted above starts my .91 and 1.20 four strokes just fine and can be charged up in 30 minutes at the field if needed.

Axiom7

i already have already invested in glow from many years back. Don't have a lot of money right now so glow is it for me right now. I'm sure I'll get into gas at some point.

aspeed

I have one larger plane with a .91 Surpass, and while it is fine, it just takes up too much room in my basement with the other 40 planes hanging on the wall. I will not buy anything that will not fit in the car or PT Cruiser, as the van is on it's last legs. I think electric may be a good choice over gas, for me. I kind of like the idea of the diesels too, but my wife is really crazy about the ether smell. They put her out with it for surgery as a kid, and the smell still bothers her today. I might try a 2200 LiPo I have just to see for the starter. I know the starter is OK with a car battery.

marmalade1

Was the 850mAh 3S Lipo for just the fuel pump / glow starter or was it also wired for the starter too?

I've got 3 similar batteries and I've thought about using them as all-round field box batteries. I realize they're small capacity, but I typically only use the starter briefly at the start of 3-6 flights.

Any thoughts?

PD