larrysogla

With all the advantages(very high discharge rate, fast charging, safe to handle etc.) of the A123 batteries............how come they are not as popular as the Lipo batteries in hobby applications??? Is it the cost??? Are the manufacturing rights(patent rights) held by only one company??? Thanks in advance for your valuable reply.
larrysogla

Capt Lou

Larry:

My personal view is that people are not yet that familiar with A123 batteries and/or are reluctant to make the investment in a pack and new charger until their current packs are no longer useful. I have been into A123 flight packs for two years and only learned about them by accident from an electronic techie who I fly with and belongs to my local Club. He and I have been big proponents of these packs but in the two years that I have been using them, only about three other guys out of 35 in our Club have swithced over to them. When they do find out about the battery, as I stated, it is their reluctance to make the increased investment when they already have nimh/nicads doing he job. I have also had people express concern about the A123 voltage rating. At 6.6 volts, A123 packs are .6 v higher than most servos and electronics are rated for, but, if you contact the manufacturers of these products you will discover that they can handle the extra .6v.

I think these battery packs are the best. In my giant scale planes I use 2300mah A123's for the ignition and two packs for the flight pack. I also bought a CellPro Multi 4 charger. If you want to read more about these batteries and find a good supplier, go to www.hangtimes.com

KW_Counter

Larry,
I think you are mostly right - COST.
The batteries are more expensive.
Then you need to buy a regulator, add $20.
Then there is possibly the need for a new charger, add $50 (if you use Hobby King).
Capt Lou isn't wrong - many in our hobby are slow to change.
I like change and am looking at LiFe but the cost is an issue.
Give it time, LiPos were very expensive once.
Good Luck,
KW_Counter

larrysogla

Capt and KW,
Thanks for your valuable reply. I am into both glow and electrics. Are there airplane propulsion motors that are A123 voltage compatible that are in the market right now?? Thanks for your valuable reply again.
larrysogla

Capt Lou

Larry:

Sorry, I can't answer your question regarding electric motors as I'm not into electric, just giant scale 50cc gas

N1EDM

My Feedback: (2)

Does anyone have any idea as to the discharge rate of these cells? I had a 5S pack in my Sig Rascal 40 and it did not perform the way I had anticipated. The batteries were given to me and were in good shape, but I wonder if they just didn't have the oomph that I was anticipating?

Bob

snellemin

I've been using A123's for while and I get about 30C contiuous and 80C burst.

I've heated them up to 193F. Vented a few with crazy amp draws(depleted within a few minutes). But never seen them explode.

guver

My Feedback: (325)

My guess is size and weight.

oops, yea I forgot cost.

gboulton

My Feedback: (15)

As one who has recently been "prodded" to change to A123,...and didn't...I'll give you my reasons.  Most are in line with what's been stated before, but there's a few other thoughts as well.

nonstoprc

My Feedback: (90)

Some other factors that make A123 less popular than lipo:

1. shape (limit to cylinder form only). Hard to make a pack as compact as lipo
2. cost to own ($13 for a single 1100mah A123 cell (max 30A discharge), while about $6 for one 1300mah lipo cell (same discharge rage)

(Price info is from hobbyking.com as of 3/13/2010)

huck1199

We are waiting for Nuclear Fusion

Mikecam

All the guys at my field pull out there lipos to charge them. I didn't want the hassle. I charge and balance right thru my switches. I use the A123 unregulated, so weight is closer when you add the regulator to the lipo as well as making it more complicated, I like simple. 1000 charges on a A123 as well as years of service, so longevity is not an issue and you can leave it for 3 months and go fly, the charge is still there. Put them away for months with no special needs.
I've seen one plane burn after a minor crash and 3 years ago a fellow club member almost burned down his garage (his plane smoldered). Do a search on battery fires and come up with your own conclusion.
I only started in this hobby two years ago so it was easy for me to pick A123's as I had no equipment that would become obsolete. An important factor in the equation.

http://www.hangtimes.com/a123_batter...iants_faq.html

rcairflr

My Feedback: (44)

I've been using A123 on my giant scale airplanes for two seasons now. IMO there is nothing better for this application. I don't think they are as uncommon as some people think. The FG website deals more with giant scale than RCU, and it seems like almost everyone on that website uses them

The cost of outfitting a giant scale airplane with A123 is very comparable to the cost with good quality Nimh and definitely cheaper than Li-po, since a regulator is not required with A123 and definitely safer than Lipo (no fire hazard)

The A123 will also outlast any other battery chemistry.

nonstoprc

My Feedback: (90)

I agree A123 packs are good for receivers/ignitions. The use of A123 packs for electric powered planes (e.g. 2M pattern) is rarely seen.

hanko

I think most peeople going to A123's will be graduating from nicads, and Nmh. If you have all the Li-Po stuff might as well stay there. A123's were around for a while before I made the change, and if I knew then what I know now I would have changed earlier.

KW_Counter

Larry,
Question: Are there airplane propulsion motors that are A123 voltage compatible that are in the market right now??
Answer: Yes, for flying electrics just use the A123s as you would a LiPo. No need for a regulator.
I mentioned the regulator as I am contemplating A123 for a receiver pack.
I don't want LiPo here because of the need to remove battery for charging.
With electrics your ESC should handle the regulator issue.
I hope this helps.
Good Luck,
KW_Counter

rcairflr

My Feedback: (44)

A regulator is not necessary when using A123 for the receiver, as long as the servos are rated for 6V

nonstoprc

My Feedback: (90)

Me too. I have been using A123s on my gas planes for over 3 years. But I doubt I want to use them on any big EP planes. To get the same capacity (say 5000 mah), you need more cells. This translates to more weight.

Even an EP 110 size pattern ship with lipo batteries will be around 10.5lb. With a YS110, it is about 9.5 lb with fuel.

dirtybird

My Feedback: (5)

I would say A123's are more popular than Lipo's for receiver batteries mainly because a regulator is not needed. That is, for people that know what they are doing.
They are not as popular for EP because:
1) They come only in two inconvenient sizes.
2) You cannot buy them in a hobby shop.
3) You have to make up your own pack that requires balancing wires to each battery.
4) They cost more unless you get them off of Ebay.

One of the distributors tried to market them thru hobby shops but they charged more than $20/cell. They didn't sell well at that price.
I use them for EP but only certain size airplanes work well due to the limited size of the cells.
BTW they do need balancing

pilotpete2

Same here. I use lipos for my E-powered planes and 2S A123's for my gasser and now my glow powered models.
While I have no fear of lipos ( I use Cellpro 4S chargers both types), I would never consider mounting a lipo in one of my wet powered models. The need for a regulator when powering an on board radio system from a 2S lipo is more than enough reason to forgetaboudit
Pete

mehrshad

123:
heavier
more expensive
larger
limited sizes and capacities

Mikecam

Hey mehrshad, you forgot safer! Just having some fun, Mine are gassers so the A123 for receiver's/servo's work great, all electric I have no experience so no opinion.

http://www.rcgroups.com/forums/showt...hreadid=149283 Love the lipo code of conduct, especially #3, 4 and 5. Charge only in fire proof container with extinguisher
at the ready and transport lipo in same fire proof container.



Here are a few more issues.



http://www.rcgroups.com/forums/showt...hreadid=186247 Scroll down to post #13

mehrshad

I agree.
I was speaking about their cons.
sure there are some pros:
safer
more efficient
faster charge
....

thank you!

StevL

Interesting thread...

I'm currently building a new 35% and I didn't choose A123. Thought about it for a long time, even lost some sleep over it. I just couldn't pull the trigger on A123 for one simple reason; I can't load check the batteries and know where I stand. Not in the option list but I went back to my trusty LiIons on regulators... never had a problem with these.

Steve

Mikecam

Yes and no on the load test. No you can't load test them with a standard load test but with a voltmagic it will tell you when it is time for a charge. I have one on my EF Yak and it does many things other then just telling you how much charge you have. I use it just like a voltwatch on my nimh. It also records the minimum volts that my receiver see's in a flight as well as the number of failsafes or glitches in a flight. It has 20 adjustable ranges so you can adjust it for your setup. For A123's there are 3 different ranges. I set mine to the safest range so I have lots of warning before I hit the dropoff. I also use the FMA CellPro Multi4 charger that acts like the load tester for your nicd, nimh, just plug it in and it will tell you in a % how much gas left in the battery. It's that easy.

http://www.voltmagic.com/