Larger 3s batteries

[Charz]

For those who are still sticking around with their 3s setups, have anyone tried batteries with capacities above 3000 mah on their mini's? I have always been fond of increasing flight times, still being in the soft 3d dept, I never witnessed those 3-4 min flight times that some folks mention (even on 6s setups).
With my ol-trusty 2700 TP 3s batts, I normally get up to 8-9 min after pumping the hardest 3d I could. However, That wasn't enough for me, so I came across couple of battery options having higher capacities and they were quite interesting. One example is a whopping 3700mah 25c batt from zippy that weighs only 260 grams, almost as heavy as a 1300 6s batt, and fits the space. I ordered this and another 3300 batt and gonna try'em out as they arrive.

I know that 6s setups are more efficient than 3s ( not starting a debate here ) however, having so many options for the 3s that fit the size and weight constraints of the Mini P is quite tempting.

Just wanna get some thoughts on this..

[sp00fman]

Nice find!

I was planning on using the Zippy 3s2800 30C on the miniP. They are 230grams and I really like them on my 450, and can use them with my Hurricane in series.

That 3700 does look pretty tempting! I must play around with some extra weights to see if it will be workable for me.

[Charz]

sp00fman, your 3s 2800 batt weight is perfect . My TP 2700 25c batts weigh around 185 grams and with them pushed all the way forward, I still have to put in a 30gram weight inorder to get the CG right. So batts in the 240 gram range should be perfect for my Mini P at least.

Hope those 3700 zippies weigh and measure as marketed. If all fine I may get more than15 min of flight time at intensive load. Only real testing will tell.

[dr dremel]

8-9 min 3D on 2700 really makes me wonder. I have the zippy 2800 and the flat zippy 2650s on my MiniP and after 6 min of loops, rolls, inverted climb outs the batts come down @ 3,75V. I´m still taking it easy with quite low HS (around 2400) so these numbers don´t add up for me?

In direct comparison I found the 2800s lacking a bit of pop, 2650s (especially 45C version) were more lively. I don´t have the bigger batts you mentioned but thought I leave this here.

For the fitment of batts I folded some cardboard boxes with the measurements from HK. All of them were spot on, some batts are even a tad smaller than advertised. From what I tried I think anything bigger than the 2650s would give you problems fitting them under the stock canopy though?

[Charz]

With My TP 3s 2700, I fly at 2800 HS and do loops, rolls and hard circuits for around 8 min before a cell reach 3.3v (9-10 min on 2600). You stop at 3.75v hence you get shorter flight time.

Also my 3s 2700 are the same size as the regular 2200 ones and there is so much room for larger 3s batts in the Mini. I had a Turnigy 3300 mah batt which I managed to fit with ease.

Folded cardboard boxes may not reflect the situation accurately as batts have rounded edges - well unless you are looking for plastic protection.

[Thalios]

3.3v!!!

Wow, you're over draining your batteries...

[dr dremel]

The 2800s are also very compact, but I figured the size of the flat 2650s was the limit. Cables come out at an odd angle and room in the nose is a little narrow. My CG with the 2650s is spot on so I did not further look into other batts. Thanks for the heads up, looks interesting. Keep us posted please!

For the 3,3V: I figure "TP" is for Thunderpower, should be good quality packs. Do they show any ill effects when draining them to that voltage?

Cheers
Dremel

[sp00fman]

You could also put the lipo with the lead upward, where there is more space on the sides. (i assume)

Some time ago i started to shorten the leads on most my lipos saving some weight. Later regretted it as it is a bit more difficult to run them in series on my larger heli. It saved around 6grams per pack.


The 3700 is still something i would like to try. but i might get my heli to heavy to perform properly.

Equipment i have set aside for the build is 20g cyclic servos, 30g tail and the 60g YEP ESC.
That is already a bit more weight than say a lighter stock setup with 60A YGE (35g) and 15g servos all round.. that is 60g difference. The 3700 is 60g more than a highC 2200mAh pack at 200g.


That's 120g more than a lightweight build.

The lipo rating itself would be fine.
Comparing:
40C x 2200mAh = 88A continoiuse
25C x 3700mAh = 92,5A continuous

[MyRCode]

Can anyone post some links to good places to get some 3S lipos? HobbyKing USA wherehouse is out of the Zippys and I can't find a good place to get ThunderPowers.

[Thalios]

msh-direct.com

The Desire Power packs are awesome.

[Charz]

OK. I finally got my 3700's . After replacing the stock bulky connectors - around 10 grams! - the overall battery weight came down to 240g, so, the overall heli weight is now 930 grams - mine has the sk540 which is bit heavier than plastic FBL's.

I also figured a simple trick to get them to fit loosely inside the canopy regardless of the wires direction. This may also be useful for those using 4s batteries. Basically, I place a little peice of light foam so that the front tip of the battery is lifted up by 1/2 inch. That's it.

I am charging my camera now, so I'll post some nice pics of my setup tommorow hopfully.

[sp00fman]

That is great! i'm getting some

Would also work amazing on my hurricane if they are only 240g.



Edit: $15 shipping cost from HK. I think ill wait a bit to see if they will be stocked locally soon.

[dr dremel]

240g sounds promising, CG should be good. I thought I would have to fabricate a hump for the 2650s also, but they did fit without it.

[Charz]

Ok, well.. didn't realize wife had taken my camera, so had to take pics using my tablet, hence the bad image quality.. but you can still see the yellow brick .

Edit: the battery weight is actually 250g not 240g. realized the scale wasn't calibrated. Heli weight is 940g - Mine has the extra thick fusuno cf frame and a DIY painted canopy which may contribute to little more weight than usual. CG is good, only a bit towrads the nose - only a bit.