Dji s800

[nigelbrogan]

Hi guys,

What size battery's do you use? Where. Do you buy them from?


Thanks Nigel

 

[olof]

I use 6 cel Pulse 5500's from AerialMediaPros.com:
http://aerialmediapros.com/store/in...ectors-c-29?osCsid=8fa8h9592o3nsg09tigmhvmn85

I also have the Exotics 6000's, they work equally well.

I fly them in parallel pairs, I do have the Zen, Iosd and 5.8 VDL as well, so the 800 is pretty heavy. I get 12 minutes flight time with this setup, I normally land after 10 minutes with 40% left on the Lipos.

View attachment 10772

View attachment 10773

 

[hjls3]

i am running the exact same setup as Olof (lipos and bird). I get great results and like the idea of running lipos in parallel. However, I fly so much at altitude - like above 10k asl - i am wanting to put my bird on a diet and see if I dont get a bit better flying characteristics. Id be ok if i lost a bit of time too save some weight. So I am going to try these guys -
free fly 6s 9000mah - http://www.quadrocopter.com/FreeFly-LiPO-6S-222V-9000mAh-25C_p_871.html?AffId=2
exotic 6s 10200mah - from aerial media pros - but i cant seem to find the weight of that guy...anybody know it?

 

[EastCoastJib]

curious as to how you balance those while charging? I have one balance port right now per channel on the icharger 4010Duo.. would love to see a picture of your parallel cable you use on the bird itself.

 

[ProPilotWannaBe]

I fly with a pair of Turnigy 6S 6000mah in parallel. I get about 15 mins on those. I also have two 6S 8000mah, but haven't flown with those yet.
As for me, I don't charge them in parallel, just fly them in parallel. I hook each one up to my 2 port ThunderPower charger.

 

[olof]

curious as to how you balance those while charging? I have one balance port right now per channel on the icharger 4010Duo.. would love to see a picture of your parallel cable you use on the bird itself.

The flying cable is just a simple paralel Y, you can make yourself or buy. The charging is not done in parallel I use either my 4 position Hitech or my Hyperion charger, and always balance charge all my Lipos.

When on location I run these chargers from marine batteries in my truck or off a small generator, if I need to charge on location. I also plan to get a solar 12 volt charger panel to charge the marine lead acid gel batts.

If I charge while traveling I always have the lipos in a fire safe bag. And when possible outside the truck fireproof ground. Just in case...

View attachment 11984

 

[maxwelltub]

I charge in parallel using the balance boards from epbuddy.com. Works great and has changed everything in terms of charging practices.

 

[ProPilotWannaBe]

Yeah, I've always been near the fence on that issue, but I am with Olof in that I backed down with parallel charging. It is convenient for fast charging, and doing it on occasion isn't bad. The problem is that, if that is the regular practice, you totally loose sight of the internal resistance of each cell, and no control over individual charging of each cell. So you may have a cell in one battery that is dying, and you wouldn't know about up front.

 

[maxwelltub]

Well with the balance board you are balancing the each cell also. I usually double check IR as well as balance individually when i am back at my shop and so far have not noticed any degradation or excessive wear. But I'm interested to hear your concern, because its something I have become accustom to

 

[ProPilotWannaBe]

Well, yes and no. You are correct that the balance board and the charger are differentiating between cell #1, and cell #2, etc. However, all of the cell #1's are connected in parallel, so the charger is seeing one conglomerate cell #1 and the "average" of all cells #1. So if cell #1 of battery A isn't keeping up with his buddy cell #1 of battery B, then the charge will end with that cell under charged (or the other one overcharged); or one cell may be dead altogether, and the charger wouldn't know it. No biggie once in a while, and if each battery is monitored. And it sounds like that is what you are doing when you said you balance them individually back at the shop and you are looking at each battery's health.

Just FYI, I am not speaking out of personal experience. This is purely what I have read and/or discussed with other operators that know more than me. Even though some of the people I've talked to do not like to do it at all, I still contend that once in a while, and if they are individually being cared for, then it is a very handy quick charging solution.

 

[maxwelltub]

Interesting, I seemed to think that it was like filling up two cups of water, if one fills up faster it spills into the other to equalize. Anyway can never be over cautious with lipos. Thanks for sharing

 

[maxwelltub]

Check out this FAQ from progressiveRC regarding parallel charging. http://www.progressiverc.com/faq

 

[ProPilotWannaBe]

Yep, good article. The only problem is that the author is glossing over IR and what a large disparity of IR will lead to, or if one cell is dying/dead. If I come across the article that addresses that, I'll post it.