The Brown one is 3000Mah, the white one is 4000Mah

Let me ask you, what is the difference between the two?

Do not go for the obvious like size and color, both batteries are the same width and height but the white one is less than half the length.and about half the weight as well.

They are also both the same voltage, but the brown is 14v 3000Mah

the white one is 14v 4000Mah.

In case you didn't know these are lithium Ion batteries.

They charge to the same voltages and discharge to the same voltages, they can be used with the same chargers as lithium polymer batteries but as you can see are much smaller and more durable.

This is because they are similar to AA batteries, they have a metal casing.

This means any crashes are less likely to kill your battery.

So I will be building these packs to sell on for you guys.

You can build them yourself if you like just have a google for some sources to buy the cells from.

I am planning to sell 4500Mah 4s size wise they are a tad smaller than a 2200Mah 3s Lipo and a bit lighter.

I am aiming to sell them for about £8-£12, a equivalent lipo

(cheapest on hobbyking was £21.50)

And 4s 1000Mah

This is about half the size of the white pack above.

The reason i wont be selling the white pack 4000Mh 4s is due to supply issues but i may in the future.

but in the future i want to expand

3s 45000Mah

3s 4000Mah

and custom batteries will also be on the agenda.

If you are interested in these packs, have a look on blog history, another member of DIYdrones has posted about them previously,

and if you would like to buy a pack now, i will start selling the 4500Mah packs in about 3 weeks after further testing and built technique experimenting.

Just PM me.

Hi Jared,

Usually I don't respond or even pay attention to DIY Drones anymore because it has become a forum for social interaction rather than a technical forum and it is refreshing to see this type of post. Also, I really miss Jack Crossfire's posts on things like this. Since most of what is posted on DIY Drones for the last several months has just been endless repetition of the same old same old.... Jack if you are paying attention to this post, your thoughts would be helpfull. You tell it like it is with no BS and are always spot on for meaningful and useful insight for this forum. Anyway, I have not responded to a post for a long time; but, your batteries peeked my interest. 1st: What Stephen Gloor stated should be an obvious spec that we need to know more about: energy density is what I am interested in as well. 2nd. Pack geometry and it really needs to be a geometry that is consistent and simple, not irregular. 3rd. internal resistance and leakage rate, have you checked that? 4th: Please provide power output in watts under some meaningful load, say for a variety of several brushless motors with several props (counter clockwise rotating pairs would be even better). It is pretty easy to measure performance under load and compare it to some commonly available lipos, like Thunderpower, etc. I suggest using a dynamometer, such as discussed on http://www.rcgroups.com/forums/showthread.php?t=2015010 (American Hobby Products Dyno - a torque reaction pendulum with a sine weighted dial for read out). I have never liked the reference to the ubiquitous C rating, which seems like a way to overly simplify a critical performance parameter for power, and is just verbal subterfuge. Why the RC community uses it, and why the DIY Drone community has adopted it, is just stupid. We should look to meaningful units for discharge under specific loads versus time and charging capacity, including the energy loss as heat, etc. NOT the oversimplified C rating of batteries, which are just a marketing ploy and are really meaningless. C values can not be used as an objective comparison for battery performance under load or energy density.

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Comments

Gary McCray May 31, 2014 at 9:19pm

Hi Stephen, especially in multicopters, a few current limited (on input) super caps could make a real difference with the Lith Ions, great idea.

Actually need a current control scheme for LiPos and super caps could very well figure into that.

Often with multi, you need a short sudden surge of power for stabilization in gusty winds in particular.
Stephen Gloor May 31, 2014 at 6:17pm

Really good site Gary - we need more like this. I have the spreadsheet that I used to calculate it that also has some more stuff to see the changes in cell counts etc. It also has a bit at the bottom on ultracaps that I was thinking of using to bolster the Panos for high current applications.

http://www.maxwell.com/products/ultracapacitors/products/k2-series

In parallel with the Panasonics they could stop the large current pulses over 2C that can damage the very light batteries. Have not done it yet however it is something to think about.
Gary McCray May 31, 2014 at 6:04pm

Hi Stephen,

I copied your excellent battery data into an HTML table and referenced it in my drones are fun battery page.

If you would look the battery page over I would appreciate it: http://dronesarefun.com/BatteriesForUAV.html

I am happy to edit it as you might think it needs, I am trying to make an actually useful and more permanent battery information resource.

This also goes for anyone else who might be interested as well.

Best Regards,

Gary
W. Joe Taylor May 30, 2014 at 10:11pm

Hi Jared,

Usually I don't respond or even pay attention to DIY Drones anymore because it has become a forum for social interaction rather than a technical forum and it is refreshing to see this type of post. Also, I really miss Jack Crossfire's posts on things like this. Since most of what is posted on DIY Drones for the last several months has just been endless repetition of the same old same old.... Jack if you are paying attention to this post, your thoughts would be helpfull. You tell it like it is with no BS and are always spot on for meaningful and useful insight for this forum. Anyway, I have not responded to a post for a long time; but, your batteries peeked my interest. 1st: What Stephen Gloor stated should be an obvious spec that we need to know more about: energy density is what I am interested in as well. 2nd. Pack geometry and it really needs to be a geometry that is consistent and simple, not irregular. 3rd. internal resistance and leakage rate, have you checked that? 4th: Please provide power output in watts under some meaningful load, say for a variety of several brushless motors with several props (counter clockwise rotating pairs would be even better). It is pretty easy to measure performance under load and compare it to some commonly available lipos, like Thunderpower, etc. I suggest using a dynamometer, such as discussed on http://www.rcgroups.com/forums/showthread.php?t=2015010 (American Hobby Products Dyno - a torque reaction pendulum with a sine weighted dial for read out). I have never liked the reference to the ubiquitous C rating, which seems like a way to overly simplify a critical performance parameter for power, and is just verbal subterfuge. Why the RC community uses it, and why the DIY Drone community has adopted it, is just stupid. We should look to meaningful units for discharge under specific loads versus time and charging capacity, including the energy loss as heat, etc. NOT the oversimplified C rating of batteries, which are just a marketing ploy and are really meaningless. C values can not be used as an objective comparison for battery performance under load or energy density.
Developer

Bill Bonney May 30, 2014 at 8:17pm

"Imagine what you could do with 49V at 40,000mAh. The largest packs were 100Ah. That’s nearly 5000Wh! Incredible stuff." Yikes :-o SparkFun at "The Battery Company"
Developer

Bill Bonney May 30, 2014 at 7:41pm

After watching this video http://diydrones.com/profiles/blogs/how-lipo-batteries-are-made-wit... Quote was something like "6 millions Pounds of pressure is applied, but things get lost in translation"

Also, charging cells in parallel, when they are not balanced can be an issue. There's this interesting article on RCGroups about parallel balance charging http://www.rcgroups.com/forums/showthread.php?t=157641

I think there really needs to be some caution when we use batteries that don't have these kinds of protections. My Li-Ion phone batteries have built in short-circuit, over and undercharge protection.

Electric car batteries have a monitor on each cell.see http://en.wikipedia.org/wiki/Electric_vehicle_battery

It would be nice to know a bit more about the specs of these batteries being used and configuration.
T3

Ted Van Slyck May 30, 2014 at 6:09pm

Maybe I missed it, specifically what cell are you using?
Stephen Gloor May 30, 2014 at 5:39pm

BTW the second column is the Amp/Hr capacity.

Stephen Gloor May 30, 2014 at 5:37pm

The key thing is the energy density so how much to the cell weigh? The huge advantage of the Panasonic cells is that they are very light for the energy that they can contain - you can manage the low discharge rate by increasing the cell count however you cannot change the mass.

	Volts	Amps	Mass	W/Hr	W/Hr / kg
Panasonic Li-Ion	3.6	3.2	0.047	11.52	245.11
Zippy Compact	22.2	5	0.703	111	157.89
MaxxAmp	22.2	11	1.235	244.2	197.73
MaxxAmp MultiVoltage	3.7	5.4	0.131	19.98	152.52
Horizon Fuel Cell	32	10	0.47	957.45	450.00
A123 AHR32113M1Ultra-B	3.3	4.5	0.2	14.85	74.25

These are the energy per kg values for some battery systems out there. As you can see the Panasonics carry almost twice as much energy as the normal Zippy battery. The MaxxAmps are better and if you can afford a fuel cell then you get two or four times the energy for a given weight. A123 batteries are very high discharge capable but also very heavy.

Until I get a cell weight I cannot calculate the energy density and compare them to the Panasonics.

Moderator

Ruwan May 30, 2014 at 3:28pm

I could be wrong, but individual cells seems to have different dimensions than AA. More like couple of 2CR5 batteries combined ;-).
Please keep on sharing your findings. I'm interested buying/getting this for my next quad!

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