gi8u2racing

My Feedback: (11)

I have taken a little time off away from the hobby, and I am finishing up a 40% size project, and went to order Fromeco Li-Ion cells as I used to use, and saw that they are on a shortage of cells, and not making packs. So what is a good substitution for these? I see some are running the A123 systems, can someone give me some suggestions? I need 5000+ mAh 7.4V packs. I have the regulators and everything already, just need the batteries. I'd like them to be shaped like the Fromeco 2 over 2 cell configuration if possible.

altavillan

My Feedback: (1)

http://www.sincityjets.com/store-categories.htm <Here's where I got started with a123. Good people.
Also Duralite is making self balancing packs. they would be worth a very serious look.
Keep in mind a123's recharge in about 10 minutes, put out twice the amps of any other battery and don't have any recorded nasty habbits. (ie. burning your house down, or causing your RX to reboot in flight) 2 x 2300 mah packs will be plenty, but get a mah counting charger and a good v-meter.

Steve

My Feedback: (54)

I just ordered a set of Duralites so I know they are in stock.

Flyfalcons

Well they do have one nasty trait in that you can't reliably check your battery voltage before flight.

altavillan

My Feedback: (1)

Yes you can check with a voltmeter. Knowing they cliff dive around 6v I feel comfortable drawing them down to 6.4v before recharge. My batteries consistantly drop volts each flight. at 6.4v I've used about half the packs power. Futaba sells a nice simple to use meter.

jfeenin

Do A123's require any sort of special charger?

Bill Hatcher

My Feedback: (2)

Troy Build Models still has 5200mah Li-ions in stock.

SunDevilPilot

Just order them from Fromeco. There is a "shortage" not an all out stop of production. I ordered mine from Fromeco and obtained my packs about a week later. My order was placed when the site said there were no cells available. You will recieve your stuff, you just might have to wait a bit.

SunDevilPilot

drewbags

I too recommend the A123 cells, simple to use no regs etc. All batteries have at least one nasty habit and as long as one is sensible the cliff dive shouldn't be a problem, especially as you charge these at 10A for a quick charge at the field if required.

On my EF YAK 110" with 9 digital servos I am using 250-280ma each 14 minute flight, so I can get plenty of flying before having to worry about a recharge or top-up.

gi8u2racing

My Feedback: (11)

I think TBM is using the second tier cells. The A123 cells appear to be the way to go. This is actually on a UAV, and this is for the prototype, so it'd be nice to keep as much consistent in the future, and we need it now, so Fromeco Relions seem to be out as an option. I already have it going through a PowerBox with Regulators, so that isn't an issue. I am between A123 and Duralite I guess...

altavillan

My Feedback: (1)

I should have said Duralight is making self balancing a123 packs. That, makes them an evan better option cause more non a123 specific non balancing chargers can be used. But if you are planning on using another balancing type charger, ie. Cellpro, then avoid the Duralights.

Zeeb

My Feedback: (41)

Yes with the exception of the Duralites as Altavillian noted. You can use your Duralite Li-Ion charger with those but the caveat is that the Duralite chargers only put out 400 mah per port.

The issue is that the A123's have a lower nominal voltage than the other Lithium type batteries, but they can also take a much higher charge rate. So the chargers for A123's have that different firmware and depending on how much you want to spend, can charge A123's at up to a 10 amp charge rate.

Makes for some REALLY short charge times......

jfeenin

So what chargers would you suggest for A123's in general? Not that I plan on switching right away, I just put Fromeco Li-Ions in my big plane so until they are worn I'm not likely to replace them but for future use I may go A123's. Also what is the fully charged and no fly (under 1A load) voltage of the A123's?

Zeeb

My Feedback: (41)

Well there are a number of chargers available now and which one you decide on has a lot to do with how much you want to spend...

There are more and more of them either coming out or being modified to do A123's. I went with the CellPro 4S as they were one of the first to support A123's, don't cost a lot and have a mah readout of how much power was put back into the battery. I'd say that last feature is a necessity as trying to load check them with only a 1 amp load isn't going to do much. Other than telling you what I use and what I think is the most important feature to look for, I won't recommend a charger as there are just too many variables to consider for each individuals particular priorities.

The discharge/voltage curve on them is extremely flat until they get to about an 80% to 90% discharge state, then it starts to fall off quite rapidly. Some have compared it to driving off a cliff and that's pretty accurate. The voltage changes you'll see will be in the hundreth's of a volt between flights, that's why most guys are just running a few tests to see what their usual usage is per flight, then recharging when that number is reached.

jfeenin

Good info. Currently I use the Triton 2 and it does show how much energy it puts into the batts but I don't think it would do A123's. I could be wrong though I don't know enough about them. I know they are a different type of Lithium base but if their nominal voltage is lower per cell as you said above I would think the Triton 2 could damage them. Thus the question about what the charged up voltage is per cell.

flyme2dmoon

My Feedback: (3)

Jon,

I highly recommend the A123s. I've been using these extensively and have converted most of my airplanes to it. I made my own packs from a Dewalt battery bought from Ebay. I'm getting rid of all my lion and regs.

Regards,
Neil

altavillan

My Feedback: (1)

Your triton will work if you get the dapters> http://www.sincityjets.com/store-categories.htm Wild Hare sells them too as do many others. Then you can charge a123 with a wall wart if you want to. As of right now a123's come in two sizes, 1100 and 2300 mah. I just got an order for some 1100 cells from my local Hardware store. They are the VPX serries Black and Decker markets with 1100 mah cappacity. I'm planning on making 4cell flight packs for a foamy and a GP eReactor. Giving them a 5-10 amp charge one should be recharged about the time the other is done.

jfeenin

More excellent info thanks.

maac16324

My Feedback: (6)

I have almost completed the move from Li-Ion's to 123's in everything from mid-size scale, pattern, IMAC and helis. I started out with the Sin City and 123 racing packs but moved to the Duralite packs when they became available. I decided to skip the make-your-own alternative out of Dewalt packs because I have little enough building time as it is without becoming a battery fabricator. My experience with the 123's has been totally positive and I cannot think of a reason to continue on with Li-Ion's.

I really like the Duralite fabrication of the 123 cells. The on-board balancing charge circuit is handy and will take up to a 1 amp charge rate. I use this most of the time because I am used to flying all day and charging at night off of a big 12v battery. Most of the time I use my standard Duralite four port charger. I also have an Orbit MicroLader which will charge at 1 amp through the charging lead or up to 4 amps through the power leads. The MicroLader is also available directly through Duralite. It originally didn't have a version of the Orbit that supported 123 cells but an added advantage of the Orbit is the ability to upgrade the charging firmware from their web site. I hooked the Orbit up to my computer and 20 minutes later I had up to date firmware and 123 charging support at no cost. The Duralite packs are available with a variety of connectors on the power leads (4mm bullet, Deans Ultra, EC3 or regular). I use the 4mm bullet connectors because they are very positive, high quality connectors that are easy to take apart. The Duralite fabrication also comes with a separate lead that they label as a "test" lead. It is just another lead off of the pack but can be routed to the Fuse side for voltage checking. One of these days I'll route it to my ignition and remove the ignition pack from my gassers. As always the Duralite packs are well made and attractively packaged. Duralite support has always been excellent for me. They are easy to get hold of and seem to care about their customers.

2.4 ghz radios and Duralite 123's have certainly made my life better since I climbed oboard.

Brian

BaldEagel

Also have a look at the Fromeco Kodiak switch designed for the A123 batteries, it has a digital read out of how much power has been consumed during flight, it adds up the readout on consecutive flights, you zero it by switching on and off and back on, uses Deans plugs on the back and front for attaching the battery to the RX and a Deans charge socket on the face, it will handle a 30amp draw, much more reliable than trying to estimate the amount of power left by voltage checking under any load.

Mike

GmanBill

My Feedback: (10)

I have no problems getting my LiIon's they are in supply and I get them ready to go, I just got 12 - 5600mAh 4 Ceil packs yesterday and they said they had plenty.

jfeenin

Who is "they"?