Henry111's free tech support thread

[bobc]

OPTO on an RC ESC has come to mean something else (than opto-isolated). My understanding is that this codeword now means the ESC does not include a BEC (battery eliminator circuit) so you somehow need to source 5V power supply for whatever is producing the control pulses for the ESC. An ESC with BEC has a 5V voltage regulator inside it.

 

[Henry111]

Is anybody using A123 batteries?
Opinions please.

 

[The Mighty Volt]

 

[CamLight]

None of your forum searches brought up A123 posts?

 

[neptronix]

No way. Nobody uses a123 here.

This post brought to you by hobbyking

 

[The Mighty Volt]

In fairness to HK they do sell A123, just nowhere near as vigorously as they do LiPo and other LiFePo4

@ OP: A123 is worthless, but I will take them off your hands.

 

[biohazardman]

You are posed to do the search for him. ;^) http://www.endless-sphere.com/forums/viewtopic.php?f=14&t=2498&start=0 Used abused and near bulletproof they are.

 

[jimw1960]

I'm building a battery right now with the A123 20 Ah prismatics. So, I will let you know in a couple of weeks. Mostly, people are using packs made from the 26650 cells, like the ones you can get from cell_man. From what I understand from folks who are using them, the A123 cells can handle 10C current draws with no problem. Nice flat discharge curve. They are rated at 30C, but I can't think of any ebike application where anyone would come near that amount of current. I think the rest of your system would melt before the batteries felt any stress.

 

[Grizzlybear]

keep your LiPo, A123s are the best batteries for ebikes, more work and skill to build, but really worth the effort.

 

[knoxie]

Pah! :lol: :lol: they are great batteries for sure no doubt however its the more work bit that leaves most folks to go lipo L I mean my pack has just 4 connections that I need to deal with and I am easily capable of making an A123 pack, the best thing about them is their charge cycle life, I dont like the multiple connections and size / capacity, availability, you also need to attach your balance wires etc etc.

Do like em though but Lipo even with its dangers do seem to be the cells of choice but I do understand folks wanting the safer chemistries

 

[dogman dan]

Well, at least you got to post 24 before experiencing the ES treatment. The ES search isn't so great, I just looked at search A123, and it didn't spit out much of use for several pages. Cellman pops up of course.

Mostly, real A123's were a bit pricy, or had to be harvested from drill packs, or other stuff. Some on Ebay were suspected to be fakes because of the high price you could get for the real McCoy. So while it was either expensive, troublesome, or downright impossible to get a large number of A123's, lipo got better and better, and cheaper thanks to hobby king. Despite a few drawbacks, there has been a stampede to lipo lately. At those prices for 30c discharge rates, 500 cycles is fine. Plus the little lipo bricks are easy to carry on the bike.

Cellman is getting a good reputation here, as the go to guy for A123's. http://endless-sphere.com/forums/viewtopic.php?f=31&t=19717

I bet many of us would stampede over to A123's if 5 ah pouch cells were common, and you could get a nice 48v 10 ah pack with bms and charger for $500.

 

[Andje]

i would have for sure. i like me some lipo, but if the A123 pouches had been available i would have jumped on em. 10c at 100v 15ah would be just fine thank you very much. I don't have the money to buy the chargers to charge lipo in the 15 mins it could be charged in anyway (the only other oft not mentioned lipo benefit).

 

[neptronix]

i would have for sure. i like me some lipo, but if the A123 pouches had been available i would have jumped on em. 10c at 100v 15ah would be just fine thank you very much. I don't have the money to buy the chargers to charge lipo in the 15 mins it could be charged in anyway (the only other oft not mentioned lipo benefit).

Eehh... you wouldn't want to charge lipo at 4C unless you had nano-tech lipo.

Anyway all battery fanboyisms aside, A123 is the better deal for sure. 3-4 times the cycle life of lipo means it is a better long term investment. There are a lot of people using it, but like dogman said, they were hard to get for a long time, though we may be seeing a resurgence.

I still like lipo though.

 

[Grizzlybear]

Pah! :lol: :lol: they are great batteries for sure no doubt however its the more work bit that leaves most folks to go lipo L I mean my pack has just 4 connections that I need to deal with and I am easily capable of making an A123 pack, the best thing about them is their charge cycle life, I dont like the multiple connections and size / capacity, availability, you also need to attach your balance wires etc etc.

Do like em though but Lipo even with its dangers do seem to be the cells of choice but I do understand folks wanting the safer chemistries

Built properly the multiple connections are no problem, I've never had a connection go bad in two years of A123 M1 pack building, I solder direct to the cells and use hyperion battery bars, Ping sells a red bms board that has no current limit, so their massive discharge capability (30c continuous) can be exploited. LiPo is becoming more popular because people are lazy, skills can be learnt, A123 M1 best batteries by far in my opinion.

 

[dogman dan]

Yep, built right, an A123 pack must be real nice. But one thing we do like about lipo is the pouches end up making a pretty tiny pack which weighs less.

Lots of it just depends on what your aim is. High discharge and small size, or other criteria like cost per cycle and lifespan. I plan on trashing my lipo in one year or at most two. Then I'll have an excuse to jump on A123 pouch packs when they hit the market. Or maybe by then it will be 200c lipo. Who knows ?

Meanwhile, to run my boring commuter bikes 20 amp controller, I'm looking at as much as 7 more years before I finally wear out both pingbattery lifepo4's.

 

[jimw1960]

All the components for the 48v20ah battery I am building with A123 pouch cells weigh a total of 18 lbs, including BMS. That's pretty competitive with lipo in the weight/Wh category. Not as cheap though.

 

[www.recumbents.com]

Yes, but where do we get A123 pouch cells now that cell_man has sold out?

-Warren.

 

[jimw1960]

a123rc.com has them for $59 with free shipping from china. I am now trying to bulk buy 100 cells from OSN power to build a couple more batteries. I will have a few dozen extras to sell if everything goes well, but don't want to offer them up until they arrive and are tested.

 

[Grizzlybear]

All the components for the 48v20ah battery I am building with A123 pouch cells weigh a total of 18 lbs, including BMS. That's pretty competitive with lipo in the weight/Wh category. Not as cheap though.

You're saving about 5 pounds against M1 cells, but pouch cells need protecting so that adds weight! Unless your racing, a couple o five of pounds ain't going to make any difference! it's like them big fat superbike road riders buying titanium parts for their bikes, they'd be better off if they lost a bit of weight themselves, lets go to extremes - take some laxatives before you ride, lose a kilogram down the bog! get real people!

A123 has many times the life of LiPo, does not need really expensive chargers, will not explode and burn your house down, you can just plug your charger in and go to bed and SLEEP, who needs more than 30c? a 10Ah A123 pack can give 300 amps continuous! 700 amps max. what are you guys running that needs more than that?

 

[Hillhater]

You're saving about 5 pounds against M1 cells, ...
...who needs more than 30c? a 10Ah A123 pack can give 300 amps continuous! 700 amps max. what are you guys running that needs more than that?

Err..? ..its not just the "C" rate or amp demand, you seem to be forgetting that most Ebikes need more than 10Ahr for decent run time (range)
20 Ahr is not a particularly big pack.
Building a 20Ahr, 60v pack from M1 cells gets to be a bit more complex than hooking together 20Ahr cells.

 

[neptronix]

A123 has many times the life of LiPo, does not need really expensive chargers, will not explode and burn your house down, you can just plug your charger in and go to bed and SLEEP, who needs more than 30c? a 10Ah A123 pack can give 300 amps continuous! 700 amps max. what are you guys running that needs more than that?

I designed my bike for 40+ mile use, so i have 20 amp hours of 36v and am looking into fitting 30ah.
There is a big weight/space difference when you compare lipo to A123 at that level.

It's a big deal if you have to carry your bike up the stairs when you're done

 

[Grizzlybear]

A123 has many times the life of LiPo, does not need really expensive chargers, will not explode and burn your house down, you can just plug your charger in and go to bed and SLEEP, who needs more than 30c? a 10Ah A123 pack can give 300 amps continuous! 700 amps max. what are you guys running that needs more than that?

I designed my bike for 40+ mile use, so i have 20 amp hours of 36v and am looking into fitting 30ah.
There is a big weight/space difference when you compare lipo to A123 at that level.

It's a big deal if you have to carry your bike up the stairs when you're done

Ever thought of making your battery removable?

 

[neptronix]

My battery is removeable. But i should never have to remove it.
It also needs to sit in the center triangle and not interfere with pedaling in any way.
Thus, lipo works really well.

 

[Grizzlybear]

My battery is removeable. But i should never have to remove it.
It also needs to sit in the center triangle and not interfere with pedaling in any way.
Thus, lipo works really well.

Of course they do, just not as good as A123, who was it that had his ones burst into flame whilst riding the other day?

I actually bought some LiPo and a charger, but they are just too much fuss and dangerous, and for what? I'd rather watch the telly than monitor my batteries charging all night.

Plus you've got to be really careful you don't discharge them too much, I really don't think you guys should be recommending them to people, you may have it on your conscience if someone you have recommended them to, dies in a fire caused by them, think about it!

 

[Henry111]

So you are doing pedal assist.
You've got seven gears.
Which gear do you pedal in?