Hi everyone. Hoping for some help on choosing batteries. Just ordered my x4. would prefer 2x22000 if possible. I live in the UK so cannot get Bonka. I have spotted a tattu 7s on eBay but the weight is 3kg. I was wondering if 7s batteries are always heavier than 6s? (1extra cell) and correspondingly higher capacity? Although on the OpenPPG shop the 6S & 7s are listed as the same weight. (2.54kg). I wouldn’t mind the extra weight of the tattu if it would give extra flight time (compared to a 6s LiPo).
Hello, the Bonka website shows 2520g for the 6S.
I can’t immediately find the weight of the 7S on their site but it will be around 400g heavier due to the extra cell.
Yes a 7S will always weigh more than a 6S when the capacity of the battery pack is the same.
Adding extra cells in series doesn’t change the capacity of the pack.
Adding extra cells in series doesn’t change the capacity rating of the pack but it does add extra flight time because you are adding more battery.
I recommend at least 4 packs to prevent over heating. Personally, I use 6 packs.
thanks for that. I would like to keep the weight down if possible… how about 3 x tattu 7s 22000? or does it have to be 4 for the correct voltage? this overheating worries me a bit… is there some kind of thermal cut-out or alarm system?? or some way of mitigating this risk?
Has to be pairs to get the right voltage.
Monitoring temperature or creating an auto cutoff doesn’t change the fact that you will put added stress on your batteries if you don’t have sufficient capacity. The best way to control heat is to use more battery (more packs or larger packs).
You could use less power for short durations. For example: climb for only a minute to ridge soar and if you sink out then climb again but only if it’s been a significant amount of time to allow the batteries to cool in between. This isn’t an option for most people.
Ok thanks. Appreciate the info. I was looking forward to a 16.5kg motor! But I can live with 21.5kg with increased flight time. That is still Less weight than most gas motors. Can I ask what the consequences with a 2 battery setup would be with the batteries over heating? Is there a real risk of Fire or is it just battery damage: if so how would it affect number of battery cycles achievable?
I live in the uk and had no trouble getting the bonka batteries
Great! Can I ask where you found them?
6S or 7S?
Whereabouts do you live?
Hi they are 6s and they were shipped throught open ppg
I am in Lincolnshire
Ah. I’m not sure if they ship now from the states to the uk?
Do you fly with 2 or 4?
I am up in Newcastle by the way.
Does anyone out there fly with 2 batteries? (2x22000 or equivalent)?
here some infos and a video 2 and 4 bonkas
Here a test with 2 and 4 bonkas
It will damage your investment. Fire is a possibility but that’s more likely to happen from over-charging them. Over amp draw and over heat will make them swell. Once they swell you shouldn’t use them for the sake of safety.
do you mean over-discharging or over-charging?
Overdischarge is the risk while flying and critical.
-one time i forgot to turn off a small drone well and checked it after about 5 hrs.
The effect was my first puffed battery that was really hot and totally destroyed.
I was really surprised how hot it was so long after beeing too empty to fly a very small drone.
I could even that battery load after 2 starts of a cheap loader but it never got full enough to stop charging but showed the right voltage when drone was turned on.
But at first start it lost power within 20 seconds to more than empty.
This was my first litium battery that was destroyed, when i see a puffed battery in the future i will not try to charge it anymore, bonkas can be repaired when you change the puffed part.
Sorry, I meant to say over charging gives the biggest fire risk. I fixed my post above.
I live in the UK so cannot get Bonka.
I’m in the UK and also want some Bonka batteries. I’ve been looking at placing a large order direct from China.
The shipping restrictions are max 35kg in a single shipment. I need 8x 22Ah 6S which comes to about 21kg. Happy to get the quote and arrange shipping to here and then forward to you and we can share the shipping charges?
If we place a large order we also get a better price.
If you’re looking for a lightweight setup, based on things I’ve read on here, you really need at least 4x batteries because of heating, but you could go for 4x 16Ah maybe? That’s 2 series, with 2 sets in parallel.
Are you looking for 6S or 7S batteries?
I’m also looking to import a charger too if you need one? I’m based near Coventry.
Appreciate the offer. However I haven’t decided yet on battery choice: As Voltaire states, 2 bonkas are no good: they heat up too much. I am torn between trying 2 of the high C batteries I mention above or giving up on the light weight option then I would maybe choose 4 bonkas but depends on cost and I might choose a 40c instead. I would prefer light weight if possible but I hear in these posts that the c rating cannot be trusted. I am thinking the “150c” will not be anywhere near to that but must be better than 25c bonkas. I was even thinking of 3 of the 150c batteries: would still be lighter than 4xbonkas. Another issue: the max amp 150c batteries are waterproof: I was wondering if this makes them more dangerous in an overheat?? (More of an explosion than a fire??) does anyone know about that?