new li-ion batteries....411

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slam
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new li-ion batteries....411

Post by slam »

o.k. i've been looking through the various threads, looking for info for the new batteries.

maybe we could have one thread with lithium ion battery info.

there has been various posts on the a123, emoli, and others. this is the power of the future, we need to get a handle on it (i have to get a handle on it[:D])

what are each batteries specs.....weight per cell, voltage, mah, charging and discharging goods and bads, and potential durability.

suggestions for battery chargers, and other info.

i am posting this selfishly, i need the info. but i think others could use this info in a central location also.

i'm off to e-zone to try to self educate.

thanks

slam
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boiler
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Post by boiler »

They do a lot of talking about such stuff over on rcgroups according to Lee Liddle.
Lee Liddle
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Post by Lee Liddle »

This is info previously posted on another thread.

There is a ton of info about these cells on RC Groups, but I`ll start this thread and try to give you guys the Readers Digest version as it relates to combat. I will also use this to document testing that I do as it relates to the various events.

Basics: Weight 70g per cell
2300 mah
Useful voltage range 3.6 to 2.5
Size Dia 1" Length 2.5"
Deliver about 2.8v under load
Discharge rate up to 30c
Charge rate up to 10a, maybe higher
Solid aluminum "can" case

Here`s a detailed write-up on making a 123 pack
http://www.rcgroups.com/forums/showthread.php?t=587606


Image

Image

Image

The cheapest way to buy these right now is to buy battery packs for the 36V Dewalt power tools. Each pack has 10 cells in it and is easy to take apart if you have a Torex #10 tamper proof driver. This is a regular Torex bit with a hole in the middle of it. These packs retail for about $180, but can be bought on Ebay for arround $100, sometimes less. They have been out for less than a year, so I would expect prices to drop significantly over the next year or so. They can also be bought from a company called 123 Racing for about $15 each. The cells in the Dewalt packs have tabs on them. The cells from 123 Racing can be bought with or without tabs.

Positives as it relates to Combat:

Hard case, not as easily damaged from crashes.
High discharge rates can allow more power for shorter run times without the expense of High C rated lipos.
Inexpensive, about 10 to 12 dollars per cell at this time
Fast charge rates, can be fully charged in 15 min or less
1000 to 2000 charge cycles (ten times higher than lipos)
Very little heat build up with charge/discharge

Negitives

Need a different charger (should only be charged to 3.6v) can be charged to 4.2 with shorter lifespan as a result, but it does not instantly ruin batteries. There is an adapter being sold for about $40 which will allow the use of a lipo charger to charge these cells.

Heavier for less voltage.
....3s 2000mah lipo weighs about 5.5oz....about 11v under load
....3s 2300mah 123`s weigh about 7.5oz..... about 8.3v under load

However you can run the 123`s at 30c (aprox 60amps) to produce about 400 watts. While even 20c lipos (very expensive) could only produce about 200 watts. So if you have the right motor you can get the same, or more, power from the 123`s as you can a lipo.
Lee Liddle
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Post by Lee Liddle »

Coppied from another thread.



Image

This is the Konion cell made by Sony. There are supposed to be three versions. The 1200mah, the 1600mah (picture), and a 2600mah.
This cell in 11/16"in dia and 2.5" long.It weighs 43g (aprox 1.5oz). It is a long thin cell which does not lend itself to high charge/discharge rates. It is supposed to be a 12C discharge and a 2c charge. So far I find it to be "happy" at about 15a discharge which is about 10c. I was expecting 18a (12c), but 10c will give good long flights.

It comes from the Makita 18v 3ah battery pack. There are 10 cells setup in a 5s2p arrangement. Cost is $99 off the shelf at Home depot (about $60 on Ebay). So the cost per cell is $10 ($6).

Since the big outrunners that many are running in 3696 draw about 16a, I thought that this might be the perfect match for 3696. However these cells seem to get too hot, and their voltage dropps too much at 16a. I did not give them any break-in time and got the first pack pretty hot, so I may have reduced it`s ability somewhat.

There was not as much info out there on this cell, so it was a little trial and error. In fact there was some incorrect info which caused me some probs at first.

A post on RC groups says that these are to be charged to the same 3.6 max as the M1 cells, but that`s wrong. These are 4.1 or 4.2v cells and can easily be charged on a regular LiPo charger.

I charge my "test dummy" pack at 2a now, and the last time it took about 1550mah. For a while I thought that I had a 1200mah pack, but now I see that they are 1600`s.


A 3s pack weighs about 5,25oz which is a little less than the 2000mah commonsense batts.

The only draw back is the lower (13a) discharge ability. This can be overcome by using a 20mm innrunner motor on a gearbox. Cash is using one and is only drawing 13a at 9k. I have had similar numbers in some bench tests.


Like the M1s, the main advantages of these cells is safety (charging and impact), faster charging(2x as fast for these cells) and longer life (up to 10x longer)

Cajun, these may be the 3696 cells that you are looking for, but you will have to run a more efficent motor than the 2809.

My thoughts for the use of these cells:

1/2a...APC 5.7/3 at 18k...I know that 3 cell will work on a 20mm motor with a 3300kz. But a 5oz pack is a little heavy. A 2spack might work with the right motor and gearbox, but then you add the weight of the gearbox. With the direct drive 3300kv motor the weight is between 8 and 9oz for the motor/prop/esc/batt combo. That leaves 9 or 10 oz for the airframe if the min weight is 18oz.

3696.... MA9/6 at 9k...... A 3spack gives about 11v at 13-14 amps. That equals about 150w. The 2908 motor need about 190w to do the job. So a more effecient motor will have to be found. That most likely means a 20mm inrunner with a gearbox, because there are no 20mm motors with 4mm or 5mm shafts that I know of. As I said above, Cash has a good combo working at 11v and 13a, so this would be a good batt for that.

SSC,,,,MA8/3 at 17.5k..... Here you are limited by the amp draw limitations of the batt (aprox 13-14). What should work is a 4s2p batt. This would be two 4s packs hooked in parallel. This would give about 14v and 27a for a total of about 340w. Each 4s pack weighs 6oz, for a total weight of 12oz. The 3s2plipos that I have used weigh 11oz so there is only a small weight penelty.
That`s enough power to do the work. It should take an inrunner direct drive of about 1800kv to hit the rpm limit, or a higher kv motor on a gearbox. There are quite a few 28mm inrunners out there for less than $65. Only a few with direct drive numbers and those all have 3.17mm shafts or smaller, so theyhave to be used as a pusher. With a strong gearbox, tractor designs will be open for
slam
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Post by slam »

o.k. here goes. this is probably going to be a work in progress

Cell type-A123
Mah-2300
Weight-70g, 2.46oz
Voltage-2.5 to 3.6v
Size-1"x 2.5"
Discharge rate-30c
Charge rate-10a
Case type-aluminum
Cost-$10-$15
3s-210g, 7.4oz
4s-280g, 9.8oz
3s2p-420g, 14.8oz
4s2p-560g, 19.7oz
+’s-cheap in dewalt pack, charge in 15 minutes, long cycle life, not much heat build up.
-’s-needs different charger

Cell type-Konion from sony
Mah-1600mah
Weight-43g, 1.5oz
Voltage-4.1 to 4.2v
Size-11/16" x 2.5"
Discharge rate-10c
Charge rate-2c
Case type-
Cost-$6-$10
3s-129g, 4.55oz
4s-188g,6.63oz
3s2p-282g, 994oz
4s2p-376g, 13.26oz
+’s-can use regular lipo charger, cheap
-’s-break-in period, low c for charge and discharge


Cell type- Emoli from Milwaukee batteries
Mah-2800
Weight-99.2g or 3.5 oz
Voltage-4.2
Size-
Discharge rate-10C-12C
Charge rate-3C
Case type-Steel
Cost-$10
3s-297.6g,10.49oz
4s-379.6g, 13.4oz
3s2p-569.4g, 20oz
4s2p-759.2g, 26.7oz
+’s-Durable, low cost, Uses standard Lithium charger, Ease of building packs
-’s-Heavy, low C capablity
Rabbit Leader
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Post by Rabbit Leader »

Hmm..might have to look at the Sony batteries. My 3696 birds are all pulling 16 amps or less at 8900-9100 rpm, depending on setup. The fact that they can be charged at 2c is still better than conventional lipos, at least what I'm flying now, and the weight's not bad. Wondering what the Sony cells would do if they were broken in, and discharged at around 15 amp? I know Lee says that 16 is pushing them, but 15 might not be too bad...might have to get a few and try it..
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Post by Lee Liddle »

Cash, I`m using the Sonys in some 3696. To keep the amps down I`m using a 4s pack and a motor with a 1000kv, 900 would be even better. I`m drawing 13 ot 14 amps static and the batt weighs 6.5oz. I don`t think that a 3s pack will do the work needed with any motor, just not enough watts available.

I`ll show you how they work this weekend, but you`ll have to look over your shoulder to see.[}:)]
Father O 5
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Post by Father O 5 »

On the A123 batteries, above, it says that you need a different charger but in Lee's post it states there is an adapter out there for $40 to be able to use a Lipo charger.

A) What charger would be good to charge the 123s?
B) Where can we get the adapter to enable to use a Lipo charger?
ZenManiac
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Post by ZenManiac »

<blockquote id="quote"><font size="1" face="Verdana, Arial, Helvetica" id="quote">quote:<hr height="1" noshade id="quote"><i>Originally posted by Father O 5</i>
<br />On the A123 batteries, above, it says that you need a different charger but in Lee's post it states there is an adapter out there for $40 to be able to use a Lipo charger.

A) What charger would be good to charge the 123s?
B) Where can we get the adapter to enable to use a Lipo charger?
<hr height="1" noshade id="quote"></font id="quote"></blockquote id="quote">
Hi Mike.

I think this is the adapter that you're looking for...
http://www.slkelectronics.com/lipodapter/index.htm
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Post by Which_way_is_up »

<blockquote id="quote"><font size="1" face="Verdana, Arial, Helvetica" id="quote">quote:<hr height="1" noshade id="quote"><i>Originally posted by ZenManiac</i>
<br /><blockquote id="quote"><font size="1" face="Verdana, Arial, Helvetica" id="quote">quote:<hr height="1" noshade id="quote"><i>Originally posted by Father O 5</i>
<br />On the A123 batteries, above, it says that you need a different charger but in Lee's post it states there is an adapter out there for $40 to be able to use a Lipo charger.

A) What charger would be good to charge the 123s?
B) Where can we get the adapter to enable to use a Lipo charger?
<hr height="1" noshade id="quote"></font id="quote"></blockquote id="quote">
Hi Mike.

I think this is the adapter that you're looking for...
http://www.slkelectronics.com/lipodapter/index.htm
<hr height="1" noshade id="quote"></font id="quote"></blockquote id="quote">


I don't believe this was the first adapter that Lee was talking about but this one looks to be a very good and simple design that can be used with about any existing nicad charger. I think that the other one still had to be used with a lipo capable charger whereas this one can be used with the thousands of existing nicad charger already out there. [:)]
Lee Liddle
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Post by Lee Liddle »

That is the same one that I referred to.
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Post by BenJammin »

Thanks for putting all of this info in one post. I'll be in the market for some E combat power come spring time.

How about chargers? I've been looking at the Duratrax "Ice" charger. It will charge up to 4s lithium @ 8 amps and costs around $120. Any other suggestions in the same price range?
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