Right up front, I am the worst at battery management.

When I started, I had No Clue about Li-Po battery management according to the
quad community which, to me, is different than normal battery practice for just
batteries in general. Normally, one charges or changes the battery when the 
device no longer operates; then use the device again until it no longer operates.
Basically, there is little to no thought about the battery except whether or not it
still works and powers a device. As for storage...what ever drawer has been 
assigned for them until they are needed. Nary a thought about it. 

Consequently, when I started FPV quads, I paid little attention to the batteries
except to charge them when they would not power a quad and use them until
they would not longer power a quad. Plus, I had no clue about "puffing". I often
had several batteries on the bench, charged, and ready to go. The only time a
battery was discharged was during flight. I was well into flying, maybe a couple
of years, before I noticed things about battery management. 

Well, I did buy some of those "storage charge" devices with good intentions or
so I told myself. Yet, I still have a couple of batteries charged on the bench and
I have yet to use one of the storage charge devices. If I don't have a charged
battery on the bench to use, then I will charge one or more. Batteries are then
discharged during flight. Any unused, normally stay on the bench as charged
batteries. When I am "taking a break", the batteries are collected up and put
in Li-Po Safe containers just as they are. 

I used puffed batteries until I learned that they were "Bad". Well, I don't want
any fires, so now, when a battery puffs, I trash it. 

To me batteries are like fuel to a car. I buy them, use them until they either 
puff or simply will not charge, trash them, and buy more. I don't mark batteries 
or count how many "charge cycles" that they get and don't pay attention to how
long that I have had them. Mostly, I believe that my batteries last between one 
and two years, maybe more. Some of them I have had for several years.

I am an endurance pilot and have always strived for the maximum fly time.
First, I fly with an easy throttle, don't do stunts, and don't "push" the quad.
In stiving for the longest fly time, I often fly until the battery will no longer
power the quad and it drops from the sky without regard for how low the
battery may have drained. In actual practice, this is might not be as bad as
it sounds. I check the battery end voltage with a meter and mostly the per
cell reading is more than 3.0 volts; often close to 3.5 volts. For me, it has
always been about the flight, not the battery. Batteries are consumable.

I do, however, charge and store my Li-Po batteries in Li-Po safe containers
(mostly), just to be safe. I am not particular with Li-Ion batteries. 

I am not recommending that anyone follow my lack of good battery 
management, but rather, simply offer my behavior as an example of
(what some would call) poor battery management; maybe not the best
for the batteries, yet, not the end of the world.

Interesting, in a way I am quite similar, I started out with whoops all 1S and no idea what I was really doing, and I have purchased a 6 Way Betafpv charger


It's a nice charger but flawed, note switch on the side 4.35V and off -- the older model of the BetaFPV 1S changer that I have seen photos of, that switch is voltage selector 4.35V and 4.2V , and now I have tested what that charger and it charges to 4.4V (Not Good), and for some time that is all I used, needless to say my 1S batteries have not lasted.

These days what I use is a SkyRC D100 V2 carger and I also have Thor 4 way chargers that basically 4 independent chargers in a charging board, and each internal charger has selectable voltage 4.35 and 4.2V and can charge a mix of 1S and 2S batteries at the same time. The bulk of my charging is done by these Thor 4 way chargers

Note that this charger only charges via the balance leads

I have tried to manage my batteries via the SkyRC D100 V2 using storage charge but is only does 2 batteries at once, and that simply didn't work for me as I am so shit at battery management, I accidently took a pack of storeaged charge batteries out for flight. (I was not happy)

Anyway these days I just charge the cells to 4.2V e.g 2S 8.4V even though my batteries as HV and I have not had an issue with puffy batteries, or batteries going bad, but I will say that I don't have the best at battery management.

This has been going well, but it had moments of quad freakout --  was coming in for landing, land and disarm, but the quad freaked out and flipped over right on land, I thought I must of hit something, as the speed up went off like a bang. Had a couple of other instances of weirdness

O.K. on closer examination I discovered the USB port touching the frame.



Partially dismantled, enough to pull the board back enough as the USB port to clear the frame, and used a Dremel tool to make clearance for the USB port and reassembled


The surprising part is I tried to tune the issue out with Betaflight --   Hmm I should have known better.

Still have the issue or freakout on landing, have carmed it down a bit via setting
set airmode_start_throttle_percent = 10
still has a freakout spike that actually blackouts the Walsnail VTX, it does come back are about 15 seconds, I don't have this problem so severe on my other quads.

Disabling airmode and the problem is grone, but no airmod, anyone have any other settings that I can try?
I don't mind a little bounce --  or course disarm just before touchdown is another solution, might just put airmode on a switch..  I might think about it.

If by "freakout" you mean it wants to self correct after bumping the ground and spins up, then that is normal with air mode and you should probably just get used to disarming an inch or two before touching the ground. With higher camera tilt, it is a little harder to judge, but if you come in horizontally and come to a stop (versus coming straight down) it makes it easier to disarm at the exact height/spot.

Depending how you have your VTX wired up, if your battery is very low and you have a sudden current draw it is possible to brownout the VTX and very occasionally I see the WS VTX go out in a crash. However if this happens often and you have sufficient voltage, then that is not normal. I've never used those washers you've shown, are they metal? I can't imagine that would be good in a crash, if you have a 3D printer it takes less than a minute to print some TPU washers/spacers. Also not sure if you top mounted the battery, that would allow the drone to land flat and maybe less air mode "freakout"?

(24-Feb-2024, 02:53 PM)mstc Wrote: If by "freakout" you mean it wants to self correct after bumping the ground and spins up, then that is normal with air mode and you should probably just get used to disarming an inch or two before touching the ground. With higher camera tilt, it is a little harder to judge, but if you come in horizontally and come to a stop (versus coming straight down) it makes it easier to disarm at the exact height/spot.

Yes I guess it normal, in this model it's very severe -- I have been flying whoops off my back porch landing on a table in front of me -- I would never do that with this model

Quote:Depending how you have your VTX wired up, if your battery is very low and you have a sudden current draw it is possible to brownout the VTX and very occasionally I see the WS VTX go out in a crash. However if this happens often and you have sufficient voltage, then that is not normal. I've never used those washers you've shown, are they metal? I can't imagine that would be good in a crash, if you have a 3D printer it takes less than a minute to print some TPU washers/spacers. Also not sure if you top mounted the battery, that would allow the drone to land flat and maybe less air mode "freakout"?

That certainly is  brownout, and I rather sure it's a combination of the BEC that I have wired to, high KV motors and the very old batteries I am flying with. About the BEC on the FC, I really didn't need to wire to the onboard BEC, it's just I didn't realise that Walksnail has upped their voltage range on their newer VTXs --
The old WS 1S VTX voltage range 3.1V-5V (V2)  
The newer 1S voltage range VTX 3.1-13V (V3)
As in this case I have the newer 1S VTX if I had wired the WS VTX -- If I ever completely pull the model apart I will rewire the power to the VTX.

For the brownout situation I have now set a motor limit of 90%, this is going to be an important setting for me when flying my old batteries.

Solutions that I have in place now, I have now gone to Betaflight 4.5 and using a feature called EzLanding.
I was inspired by this video by Drainman


Wow I have to say Betaflight 4.5 suits this setup, flying so nice    and I have now enabled
set mixer_type = EZLANDING
There must be some rather nice changes in Betaflight 4.5, flying so nice. I have been perching, landing and taking off all without disarming.

Interesting new feature, but the fact that it accidentally turns off airmode like when you are in the middle of a dive is something you should be cautious about. Since there is the accelerometer they should have also considered that a) drone is level b) rate of descent is minimal, otherwise leave air mode on.



https://github.com/betaflight/betaflight/pull/12094

add an aditional capacitator, mount the battery without the print as try = check your softmounting
(there needs to be a nut between fc and walksnailboar, the fc needs to be softmounted indipendently, the rubers flexibility does match the requirements for the gyro. not sure how you did it.)
maybe increase filtering.

if not successfull, you might get iterm windup, pids might be your issue than;
lower iterm value, adjust anti gravity gain

Just an update on the Smart25 walksnail 2.5" build, problems I have hit, and solutions so far.

I found the main cause of the freakout on Landing, and it was issue that was causing brownouts on full throttle punch outs, the actual FC would reboot.
It was my poor soldering of the pigtail to the Flight Controller. How this was showing up on landing where airmode would cause would spike a voltage drop, the flight controller I am using is a Zeus 2S-6S AIO, If was doing this again, I would use a 1S-2S controller, the reason that I was using the Zeus 2S-6S AIO that is an secondhand flight controller that I had in my spare parts bin.


The main issue was me being lazy and not using a large enough tip on the soldering iron, this has now been corrected by resoldering. For testing after the job was complete was bench testing by fixing the quad to the top of a bike stand and throttling the quad via the remote, this is a hash test and the quad would still brownout on the S2 CNHL  batteries but was o.k. on the 2S GNB batteries.



I have to say I am loving the new props I am currently using the rather aggressive AzurePower Tri Blade 254003, they are super quiet, and they have a really good sound ot them.  I might have to give up those props if the brownout issues reappear, and go back to the Gemfan 251203

I am totally enjoying Betaflight 4.5 with Ezy Landing enabled, it's really worth trying and you can certainly see the improvements in Betaflight.

I also love the Azure 2540's, but if not I tend to run HQ 2.5x2x3 or 2.5x3.5x3, which are both adequate for these types of builds.

As to landing, I just learnt to land and disarm at the right point. I've not really had any issues with bouncing while in acro, it's more an issue in angle mode. Might be useful for noobs that haven't learnt how to land yet, but I would expect most people who've flown acro for a year to be able to land without issue.

Hmm warning to self, I changed the out probs back to the Gemfan 251203 -- yeah watch the screw length the hub is smaller on the Gemfan props, after screwing down the screws, spinning the props, I could feel only very slightly the screws must be just touching windings, I quickly swapped to shorter screws, a must for this hobby and anyone building drones, get a grab kit of all different length of M1.6, M2 and M3 screws without it I would not have the correct screws.

O.K. back to the batteries, for this build I have found good quality batteries are a must. I flew Yesterday, tested with the lower pitch props, just to be sure 


I found with the S2 CNHL 550mah batteries the voltage dropping dangerously low even with just moderate throttle movement to a point that I will be no longer using the these CNHL batteries with this quad.
I found both the Flywoo 750mah and the GNB 720mah no problem at all and very little battery sag, actually so little battery sag I have to raise the battery low voltage warning.

Interesting weights of these batteries
CNHL 550mah = 34g
Flywoo 750mah = 35g
GNB 720mah = 36g

I would be interested if people have any other good quality 2S battery recommendations, particularly ones that are easily purchased in Australia. 

I would caution against the GNB yellow labelled "90C" cells. They are great when new (mostly, I've had a few arrive DOA), but bad cells develop very quickly. The 600mah pack is 27g compared to a red label "100C" 550mah which is 30g and both are HV. My red labels are new, so have not had much time with them, but hopefully they will last longer.

The new Betafpv Lava batteries look interesting. They actually post a discharge curve which seems rare for lipos. They are not HV so probably not the best choice if you want longest flight time, but should be good for sag and hopefully last more cycles.

On 2S my favourites are the ones mstc doesn't like.  I bought a few of them when I first started and they are still going strong, but have lost a touch of capacity.  I use these for 2S all the time over anything else.  For me, they are just better than most anything else I own.

Very old batteries, i didnt try the particular model, but this dinogy batteryline was outstanding about performance in my use and the most impressive was lifetime/cycles.
I would like to buy them again but they arent available localy anymore.

Personal i would like to know how they are in the 600mah version.

https://buzzfpv.com.au/product/dinogy-gr...battery-2/