AW IMR vs BIO IMR

[Sicarius]

Found this comparison and thought I would post it for reference.

The batteries are both 18650

AW IMR 1600maH / BestInOne IMR 1500maH -

Interestingly the BIO holds its voltage above 3.2V longer than the AW (Should last longer in a ProVari)

 

[CraigHB]

Neither can compete with this IMR cell. They can be purchased here. I recently came across these in checking out Pansonic's line-up. They were released by Panasonic last year. There is some debate on whether these are actually IMR batteries since they use a proprietary chemsitry, but they have discharge limits and safety similar to other IMR cells. Here's another data sheet from Panasonic's site, it has more info than the one on the first link.

 

[MastiffMike]

Neither can compete with this IMR cell. They can be purchased here. I recently came across these in checking out Pansonic's line-up. They were released by Panasonic last year.

Really? In e-cig applications? Has David tested them to compare to his AW tests? Because it looks to me like they drop below 3.5v much sooner than the AW IMR 18650 2600mAh (but I'm not very technical so maybe I'm missing something)?

 

[asdaq]

Well, the AW stays above 3.7 longer, so there is that. The Bio doesn't look to be as high drain. Also this doesn't take into account the newer 2000 mAh AW IMR's which hopefully don't sacrifice any performance for longevity.

 

[Semiretired]

The problem with most of the battery test are that they are based on a steady drain - like with a flashlight, while PV'ers do short high burst with time between the next burst so the dissipation of the energy would be different.

 

[MastiffMike]

Well, the AW stays above 3.7 longer, so there is that. The Bio doesn't look to be as high drain. Also this doesn't take into account the newer 2000 mAh AW IMR's which hopefully don't sacrifice any performance for longevity.

OK, so I'm right to not believe Panasonics marketing hype!

Now Asdaq, shouldn't you be working on building me a (free!) mod? You know, something that'll take an 18350 + Kick, and parallel to the battery would be a tank. Of course it's gotta be pocket friendly with locking button! You know, like pretty much everything you build, AWESOME!

Now chop chop, get to building so you can ship it by Monday!

 

[MastiffMike]

The problem with most of the battery test are that they are based on a steady drain - like with a flashlight, while PV'ers do short high burst with time between the next burst so the dissipation of the energy would be different.

Yeah and for a dumb dog like me it's all so confusing! The graph on the Panasonic site looks quite a bit different (and much better) than the chart on the site that sells them.

I'm happy with my AW IMRs but I certainly wouldn't mind something better! (if it was available in <650 length)

 

[CraigHB]

The AW IMR 18650's have about 20mΩ internal resistance where the CGR18650CH has around 35mΩ internal resistance. You can imply that by looking at the discharge curves and observing the voltage drop. Granted, with the CGR18650CH, you're losing more power within the cell and that can be worthy of consideration, but in this case, it's probably not going to be. That 15mΩ extra resistance will translate to 1.5W out of a total 37W at 10A. That's a loss about 4% higher than the AW IMR cell. However, the Panasonic cell has 40% more capacity so you still come out way ahead. You're looking at 36% more capacity delivered to the load.

The slightly higher voltage sag of the CGR18650CH over the AW IMR 1600mAh may be an argument for an unregulated mod, but it's a weak one. The point is totally moot for a regulated mod. There probably is not going to be enough of a difference in power delivery to be able to tell vaping. Though, you could detect it with a DMM.

The graph on the Callies Kustoms site is for the 3100 mAh Panasonic cell (NCR18650A) which is a standard 2C cell that uses a proprietary Lithium Cobalt variant. BTW, the NCR18650A's internal resistance one of the highest of any 18650 Li-Ion, around 70mΩ. To see the discharge curve for the CGR18650CH, look at the data sheet I linked to.

Granted, manufacturer information is often not real world, but Panasonic is a reputable company that has nothing to gain by fudging specs (they make the best Li-Ion round cells in my opinion). I'm sure the curves they posted are reasonably accurate.

 

[Sicarius]

Reason for posting the comparison is to bounce discussion amongst the pros.

@Craig - The BIO from a bang for buck perspective far outstrips the PANA (sort of like comparing a Intel i5 2500K to a i7 3960X). Cutting edge unfortunately comes with a pricetag.

The PANA will become the new standard I am certain, but in today's cash strapped world the BIO was an interesting competitor to the all to often bantered AW (don't get me wrong I am a fan) and at less than $4.58 each delivered it almost seems an open and shut case.

 

[CraigHB]

Yes, cost is always a consideration and the Panasonics are pricey. That's why the battery pack for a Tesla automobile costs $30k. They use the 3100mAh cells, I think it's like 6000 of them.

I'm thinking about doing a mod with one of the CGR18650CH cells and the price does set me back a little. I can get a LiPo flat cell for a third the cost, but the charge density on a high drain LiPo is even slightly lower than an AW IMR round cell.

I always build boosters and I have to keep battery resistance under 50mΩ or the booster isn't happy. That's why mods like the Pro-Vari and Lava-Tube require IMR cells. The LiPo I'm using right now has 7mΩ internal resistance. Never a problem with internal cell resistance using a LiPo.

The charge density on the NCR18650A is outstanding, but cell resistance is too high for a booster. I'm thinking of running two in parallel. That would give me 6Ah, 35mΩ battery reistance, and a 12A drain limit, perfect for a booster. That would be ridiculously high capacity but I don't think it would be terribly large. Though, $26 plus shipping for a battery sort of makes me choke. Those things do wear out so you have to replace them every now and then.

 

[Sicarius]

How about supersizing your mod

IMR26650-3500mAh 3.7V Rechargeable LiMn battery (2 pcs) $16.11

 

[CraigHB]

Hehe, that would be huge, I'm trying to go smaller, not bigger

 

[Rocketman]

A mod with a single 26650 isn't that large

 

[cd68]

Yes, cost is always a consideration and the Panasonics are pricey. That's why the battery pack for a Tesla automobile costs $30k. They use the 3100mAh cells, I think it's like 6000 of them.

I'm thinking about doing a mod with one of the CGR18650CH cells and the price does set me back a little. I can get a LiPo flat cell for a third the cost, but the charge density on a high drain LiPo is even slightly lower than an AW IMR round cell.

I always build boosters and I have to keep battery resistance under 50mΩ or the booster isn't happy. That's why mods like the Pro-Vari and Lava-Tube require IMR cells. The LiPo I'm using right now has 7mΩ internal resistance. Never a problem with internal cell resistance using a LiPo.

The charge density on the NCR18650A is outstanding, but cell resistance is too high for a booster. I'm thinking of running two in parallel. That would give me 6Ah, 35mΩ battery reistance, and a 12A drain limit, perfect for a booster. That would be ridiculously high capacity but I don't think it would be terribly large. Though, $26 plus shipping for a battery sort of makes me choke. Those things do wear out so you have to replace them every now and then.

you can get the panasonic batteries cheaper here.
Panasonic CGR18650CH 2250mAh - $7.99 : SmartVapes Electronic Cigarettes, Electronic Cigarette

 

[Sicarius]

Good price on those, but shipping is $17.95 to New Zealand. Bummer.

 

[CraigHB]

That's a great price, shipping is actual price for priority USPS so good price on shipping for me. Thanks for that link!

Don't really understand that disclaimer about not being good for regulated mods. These are the best batteries for regulated mods. What do think is better?

 

[slimest]

Don't really understand that disclaimer about not being good for regulated mods.

Yes, strange recommendation.

Added: Oh, maybe the author meant buck converters, not boosters. In this case sounds logically - first - no need in IMR parameters, second - these batteries don't have own protection boards...

CraigHB, 2 units in stock, hurry up

 

[CraigHB]

A mod with a single 26650 isn't that large

An IMR 26650 is not unreasonable, but you're gaining 8mm in width and you're not increasing the charge density, just charge capacity. I figure if I'm going bigger, I want to get something big out of it. Looking at a box type enclosure, a 26650 is going to occupy 44k cubic millimeters. Two NCR18650As will occupy 42k cubic millimeters with almost double the charge capacity. So, it takes up a little less box space and provides almost twice as much run time.

In terms of a box, you need a square 1:1 aspect for the 26650 which I don't particularly care for. Two parallel NCR18650As accomplish the same objective (able to drive a booster) while providing almost double the run time with a nice rectangular 2:1 aspect. It may be possible to use an ICR (LiCo) 26650. You'd get the same high capacity with the required drain capability and cell resistance, but that's still the less preferable 1:1 form. Though, I haven't seen a cell like that. I've only seen the 26650s in an IMR type, also LiFePO4.

 

[slimest]

TrustFire 26650 Li-ion Batteries Rechargeable 3.7V "5000mAh" (Pair) - Free Shipping - DealExtreme
Seems that these batteries are LiCo... Never heard about IMR Trustfire.

Hmmm... Callies Kustoms compared their new Panasonic IMR batteries with AW IMR. In my opinion, this short movie simply shows that AW IMR just can give more current and power, but they are not less safe
http://www.youtube.com/watch?v=haMDZOfjqsE

 

[asdaq]

Mastiff, expect that to ship monday this year.

Am going to give a pair of CGR panasonic s a try , bulk discount for 2 and a 5% code as well.