Konions or A123?

[katou]

A123 has higher C rate, Konions apparently don't require balancing.

Which one is preferred?

Konions also seem to be sold cheaper??

Katou

 

[heathyoung]

Pros: No balancing on the Konions, higher voltage (different chemistry) - fewer in series so ESR is less of a concern, cheap, pretty damn indestructable - (I've recovered cells from 0.2V sucessfully!)

Cons: Smaller form factor, lower Crate.

 

[katou]

It seems like A123 around here is going for $5-6/cell. What's a good price for Konions?

Katou

 

[Ariane]

Hi Katou,

I'm using Konions on my ebike and really like them, i never try to charge them over 4 volt and dot not try to discharge them under 3 volt and i didn't run them at their maximum capacity (10 C) if you respect them they are nice cells but their discharge curve is not flat like the A123.

For an example a 20 Amp Konions pack can output 200 amps (10C) but A123 pack of 20 amps can output around 600 amps with a flat discharge and requires a BMS for charging. Also a good point about the Konions for the same volume the have a little bit more Watts-hours than a comparable A123 pack.

Then the choice is you’re for needs and good source of Konions is Doctorbass, John in CR as good post about the Konions, good day!
Black Arrow

 

[tostino]

Im using a self built konion pack now, and it is *alright*. If I were to do it again, i'd use lipo over the konions. The discharge isn't flat, and the mofos are heavy for the energy stored next to lipo. If I didn't have as many AH as I do, I would really not like the konions for a high powered bike. It really depends on the price you can get them for!

I got the majority of mine at about $0.10/wh... So at that price, of course i'll be using them!!!

 

[Ariane]

Im using a self built konion pack now, and it is *alright*.!

Yes it's alright but not the way you have solder them and i can say that i have a high power ebike of course if you compare them to lipo pack is another story.

Good day!
Black Arrow

 

[John in CR]

The great thing about Konions is that if you baby them a bit with extra capacity and conservative charge and discharge then they're hassle free. The pack I'm running now has over 500 50% DOD cycles in the past year, and I've never even checked it for balance. I park, plug in the charger wire, hit start, and that's it, so as long as you construct a good pack and don't abuse it, they beat all other batteries in terms of hassle free.

In addition the non-flat discharge curve they also sag badly at the end. I actually like that, because it enables me to run no electronics or LVC on my bikes. All I have is a regular bike speedometer. Under load the batteries tell me I need to get home with about 2 miles of leeway if I slow down a bit. I rarely run that low, so it works like a low light on a gas gauge.

The A123's will obviously win on cycle life by a wide margin, so puts them on equal footing or ahead economically. The also win on power density and DOD. Plus you can actual buy them in quantity. The only Konions I've found for a reasonable price are used Makita packs, but supply is limited and inconsistent.

I love hassle free, and at this point I shop only on price, because I figure all I need is a year or two, at which time I expect far better cells to be available for less. My Konions are a great bridge in hopes of better batteries, BMS's, and prices in the foreseeable future.

John

 

[John in CR]

Im using a self built konion pack now, and it is *alright*.!

Yes it's alright but not the way you have solder them and i can say that i have a high power ebike of course if you compare them to lipo pack is another story.

Good day!
Black Arrow

I think Tostino got well worn packs from Marty, which were also mostly VT Konions which are much heavier for a given capacity. The V cells aren't much behind the lipos by weight, though definitely by volume. Of course all cylindrical cells give up over 20% in volume comparisons just because of their shape.

 

[liveforphysics]

Kinions are a pretty slick, pretty unique type of safety lithium.

If you can get them for the right price, they are the no-brainer choice of all the lithium safety chemistries IMO.

Pretty neat little cells with the self-balance ability. Don't under-estimate how much BMS related wiring and hassles that saves.

 

[tostino]

Im using a self built konion pack now, and it is *alright*.!

Yes it's alright but not the way you have solder them and i can say that i have a high power ebike of course if you compare them to lipo pack is another story.

Good day!
Black Arrow

I think Tostino got well worn packs from Marty, which were also mostly VT Konions which are much heavier for a given capacity. The V cells aren't much behind the lipos by weight, though definitely by volume. Of course all cylindrical cells give up over 20% in volume comparisons just because of their shape.

I used only "v" cells in my packs. I also did (basic) IR matching of the cells (no capacity matching), and didn't use any that were too worn. All of the cells I used held their rated capacity.

Hell! I still have about 100 cells sitting around that didn't measure up to what I wanted to use for my pack that are "v's", not to mention the bunch of VT's I have yet to find a use for (been meaning to build a booster pack, just low on time lately).

Also, I know soldering isn't the preferred method of pack building. Your not telling me anything new there BlackArrow. However, I know for a fact that the heat didn't do much measurable damage to the cells. The full pack still holds it's rated capacity, and the voltage drop really isn't bad. At 105a load when accelerating, I will drop from say 55v to 51v (this is from memory, and could be a little off, i'll get you actual values tonight). 4v dropped from pack (through wiring that needs to be beefed up coming out of one of the packs). Ideal? Not compared to Lipo. But your criticism simply because I soldered a pack together (very carefully in regards to heat) is unneeded.

 

[def215]

well my experiences with konion cells are good. so far they are working fantastic for me. i have a 7s6p pack on my lowered power e-bike setup and it works very well. ive have had to balance it once in a blue moon but overall, they stay in perfect balance with each other. i have no experience with a123's. if anything, i would contact doctorbass about anything dealing with konions.

 

[ambroseliao]

I've found Konions to be great cells. They are bullet proof. I drained 3 of them down to nothing (by accident) and they recover completely. The simplicity of just plugging them into your charger couldn't be simpler. They pour out power on demand and are very reliable. I have found enough packs to keep me going for a while, but a reliable source for inexpensive and new cells is not very easy, IMHO.

I am thinking of implementing a Celllog 8S to keep track of my individual Bosch Fat Packs but can't decide if this is needed or not.

Does anyone have a source for NEW Konion 18650V or VT cells???

Ambrose

 

[webfootguy]

I've found Konions to be great cells. They are bullet proof. I drained 3 of them down to nothing (by accident) and they recover completely. The simplicity of just plugging them into your charger couldn't be simpler. They pour out power on demand and are very reliable. I have found enough packs to keep me going for a while, but a reliable source for inexpensive and new cells is not very easy, IMHO.

I am thinking of implementing a Celllog 8S to keep track of my individual Bosch Fat Packs but can't decide if this is needed or not.

Does anyone have a source for NEW Konion 18650V or VT cells???

Ambrose

I was able to find a source of new Konion cells. Cost was around $8/cell plus shipping from Europe. This was in quantity of 800 or so. These cells would be "matched" meaning they were all from the same lot/batch which is ideal with this kind of cell when building packs.

 

[katou]

Wow, that's a lot of really good information, it sounds like Konions have a lot more going for them than I thought.

That "No BMS" thing is sure attractive. Cost AND reliability wise.

What is holding them back from wider use then? Maybe the high-C Sexy Factor of the A123?

It sounds like one big problem is supply though. I wonder how many cells would get sold if DB had lots and lots?

Katou

 

[ambroseliao]

I was able to find a source of new Konion cells. Cost was around $8/cell plus shipping from Europe. This was in quantity of 800 or so. These cells would be "matched" meaning they were all from the same lot/batch which is ideal with this kind of cell when building packs.

At $8 per cell, a Bosch Fat Pack equivalent would cost $160! That's for 37V 2.2AH. That's almost $2 per WH!

It makes the BFPs available on eBay at around $75 each sound like an incredible bargain!f

Ambrose

 

[John in CR]

...it sounds like Konions have a lot more going for them...

Not for $8/cell. I wouldn't go above $3/cell including shipping for the V cells, and already matched and tab welded 2p5s.

 

[scoot]

Less than a year ago I almost went the konion route when i found some fat packs on amazon for $35. I ultimately chose the Headway LFP route because I can't solder or spot weld to save myself If it had not been for that, I would have gone with the konions or even A123s for sure. However I feel like the LFP s kind of forced me to learn a lot more about batteries and it has been a fun journey to be sure.

So i can definitely see the dilemma for the OP

 

[John in CR]

With fatpacks at $35 the decision is a no-brainer. 20 US18650VT cells for $35 already tab welded with casing in a 2p10s config was a great deal last year. Where are those kind of deals this year? I didn't get mine that cheap, but I did get 10 fatpacks and 5 chargers. This year there haven't been any awesome deals, though the general prices have come way down for the better stuff, especially the RC Lipo stuff, which is starting to temp me.

 

[docnjoj]

Yeah folks! That is my thinking too. At a buck a w/h they are still reasonable if you factor in their simplicity and ruggedness. BFP were underpriced at $45 but at $75 the are reasonable given no other voodoo electronics are needed to balance them. Lipos are looking better and better every day though......... Maybe my next pack.
otherDoc