i use this Amazon.com: 3M Dual Lock Reclosable Fastener SJ3560 250 Clear, 1 in x 6 Ft: Office Products
What you got looks the same...I also secure it with a Velcro strap through the VPS...
Dual Battery Mod
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What you got looks the same...I also secure it with a Velcro strap through the VPS...
Yup probably 12awg enough, but I don't mean on the xt60 I'm talking about the single internal lead to conect the two split packs to lower internal R ... have you confirmed that with insulation you get same performance as before splitting the 4s pack? That's what I'm hopping to achieve ....
soldering a 10awg from one pack to the other ... has any one try this?
Hey Habanero, I did a before and after resistance check on the last battery I split and the 10" 12 gauge wire added 2mOhms of resistance..I check the individual cells and the 1st, 2nd and 4th cell is around 1.72 and the 3rd is 3.70 after the split...This particular batteries IR is the lowest i've seen so far...But, like i said, i don't really think it matters as long as the resistance isn't greater than the DJI battery and they drain evenly. Or now that i think about it the external is draining quicker... for example 8000mah and DJI 4450mah ending with the same voltage at the same time? My MS LiHv batteries end at the same voltage as the DJI's on the 5200 6600 or the 8000....I have to quit thinking its too early for me
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Hi Chazz what is the weight of that turnigy 8000 mah?Hey Habanero, I did a before and after resistance check on the last battery I split and the 10" 12 gauge wire added 2mOhms of resistance..I check the individual cells and the 1st, 2nd and 4th cell is around 1.72 and the 3rd is 3.70 after the split...This particular batteries IR is the lowest i've seen so far...But, like i said, i don't really think it matters as long as the resistance isn't greater than the DJI battery and they drain evenly. Or now that i think about it isn't the external draining quicker? for example 8000mah and DJI 4450mah ending with the same voltage at the same time? My MS LiHv batteries end at the same voltage as the DJI's on the 5200 6600 or the 8000....I guess they charge the DJI batt at the same time....I have to quit thinking
After the split 760grams. It was a 6cell. A little heaver then i would like but WTH i wanted to test something different...The MS 8000 LiHV after split is only 644 grams...
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I have had my eye on those batts for sometime,but seem to be heavey.thats not bad for weight.hope you see at least some good fly time.
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So let me guess you bought a 6 cell made a 4 cell with 2 extra cells.incase you have one bad cell? Or was the plan to buy 2 of those 6 cell batts and make 3 batts out of them?
Your exactly right...I was thinking both. If i like i can buy another and have 3... I ended taking out the weakest cell but they were very close so i wouldn't consider it bad at all...Maybe 1.8 ir vs 1.72...
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Hey Habanero, I did a before and after resistance check on the last battery I split and the 10" 12 gauge wire added 2mOhms of resistance..I check the individual cells and the 1st, 2nd and 4th cell is around 1.72 and the 3rd is 3.70 after the split...This particular batteries IR is the lowest i've seen so far...But, like i said, i don't really think it matters as long as the resistance isn't greater than the DJI battery and they drain evenly. Or now that i think about it the external is draining quicker... for example 8000mah and DJI 4450mah ending with the same voltage at the same time? My MS LiHv batteries end at the same voltage as the DJI's on the 5200 6600 or the 8000....I have to quit thinking its too early for me
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Thats really good find!!!! I knew it was about 2mOhms for the 12 and should go down to 1 with a 10gauge and near 0 with 8gauge... Thats really low IR for those cells, great stuff... they still have lower IR than OEM ones so they discharge faster. If IR its not a problem batteries will discharge at the same rate keeping the voltage the same , if one has more voltage that will drain until equal the voltage of the rest... its like a multiple water pumps the one with more pressure(V) can pump more water untill equal the pressure of the others draining at same time using a single common pipe....
Now the reason those batteries are so hight in amp/weight ratio its the low IR. You add IR and the ratio will lower,(energy its used to overcome R and normally dissipate as heat) in this case not much as its not much difference but if my math is close it should lose about 5-7% in total mah so in theory you lose ~400-650mah. What that may be 2-3 min? So in theory using a 10gauge should give you ~2min?
Its snowing so bad here that I don't even feel like playing with the mod to do real test , can't fly like this ;(
Good info! and good pump analogy....so i was gettin 20min with just the stock battery and 40 to 38 with my ms8000 LiHV attached lets say 19min more... that's about 7 seconds per mah so maybe 1 1/2 min extra with the 10 gauge at a gain of 650mah? Now with the affect temp has and the 10gague i would say the best would be to fly on a warm day (or at least a warm battery) with 10gague or 8gague wire...No? Now we just need to add weight in to the equation...
edit: thought of something...weight was added. 7sec per mah was with the weight. without it would be closer to that 2 to 3 min extra... i just ordered some 10 gauge to see the difference in weight and ohms...
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Getting a little too deep but another thing if you want try and figure out weight the 8000 weighs 644 grams. and the dji bat is 4480mah with an added 20min (rounded for simplicity) flight that's 3520 mah used to carry the added weight...or maybe I'm a nut and this is way off...
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Yes thats right, a few grams of difference on the wire need to go into the equation but we had also been very conservative on the #'s... so its up to real life test to figure out the gains.... Batteries will always performs better on a temp range but that we can't change only help with your insulation idea.... Weight and aerodynamics, thats why I like to split the batteries and been thinking of mounting them on the sides with and angle so when the bird its till they act as wings giving lift . Downside would be that going reverse would do the contrary but good for decending lol Im trying to split hairs here....
i like splittin hairs. gaining one or two minutes is great! Just watch the batteries don't get in the prop wash...i run them as tight as i can on the side of the legs... with your numbers im thinking that resistance pays a bigger part then weight...
insulating them only works so long...It helps with the abrupt changes in temp and holds it off but eventually cold gets in...I test them after sitting in my cool basement after sitting there for a while and the resistance still goes up by 1 or so mohms per cell...Just like the non split batteries...So i would say warm weather should be the best for the longest flight times...
real world test is going to happen next time i fly if it ever warms up around here...My new 8 batt is 116grams heavier then my ms8 but the total pack resistance is 8 mohms less...we'll see...
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I'm using this and it works well.
3M Dual Lock Reclosable Fastener SJ3560 250 Clear, 1 in x 6 Ft Amazon.com: 3M Dual Lock Reclosable Fastener SJ3560 250 Clear, 1 in x 6 Ft: Office Products
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Haven't posted in a while but I have been following along and thank you guys for keeping this thread alive, most of the rest this forum is DEAD!
I can confirm that if you try & lift external batteries without them plugged in and assisting in voltage you will receive errors.
I've been experimenting with the 10.0 ms battery with camera and while it's quite a chore for the P3 to handle,and it doesn't handle very well, it has offered some fun flights averaging 45min. & taken my camera bird to amazing distances. Every moment in the air I felt it could fall! I wrecked one a/c at the end of flight because I stopped too fast & it backflipped. It was old motors/ old fw. I tried 10.0 on diff bird, new motors/ new fw and it would not lift the 10.0 without motor overload errors. I then tried on another old motors/old fw bird and it flew!! I think either old motors or old fw can carry the heavy off balanced weight where the new motors OR newer fw birds can't without errors.
I can confirm that if you try & lift external batteries without them plugged in and assisting in voltage you will receive errors.
I've been experimenting with the 10.0 ms battery with camera and while it's quite a chore for the P3 to handle,and it doesn't handle very well, it has offered some fun flights averaging 45min. & taken my camera bird to amazing distances. Every moment in the air I felt it could fall! I wrecked one a/c at the end of flight because I stopped too fast & it backflipped. It was old motors/ old fw. I tried 10.0 on diff bird, new motors/ new fw and it would not lift the 10.0 without motor overload errors. I then tried on another old motors/old fw bird and it flew!! I think either old motors or old fw can carry the heavy off balanced weight where the new motors OR newer fw birds can't without errors.
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Holly cow that's the mother of all batteries lol . Did you fly it resting on the base of the landing gear? I did be scare to flip her with the counter weight ;-) ....
Magic motors or FW . I'm on 1.8 with old motors been considering downgrade now that it's possible... 1.6 or 1.4 ? Maybe should try one at the time ....I have to say that 1.8 it's very conservative and save but I did like to go faster and I worry about the lower transmission signal ....
Magic motors or FW . I'm on 1.8 with old motors been considering downgrade now that it's possible... 1.6 or 1.4 ? Maybe should try one at the time ....I have to say that 1.8 it's very conservative and save but I did like to go faster and I worry about the lower transmission signal ....
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It's extremely back heavy!
It wedges in so tight between vps and landing gear you almost don't need to strap it. I braked too hard on my last flight wit it and it flipped over and landed on its top. Very risky and experimental battery
It wedges in so tight between vps and landing gear you almost don't need to strap it. I braked too hard on my last flight wit it and it flipped over and landed on its top. Very risky and experimental battery
