[darkdave]

I have 2 drones, a quad and a hex. Both are small racing carbon chasis drones and both are effected the same way when I use 2 types of batteries that I have.

Whenever I use the grey ZOP POWER 30c 11.1v 2200mah brand there are instabilities like as if the escs are not calibrated and out of sync for both drones (hex and quad). When I use the other one Kudian with the same voltage and mah but a lower 25c the drones are stable!

What gives?

Is the lower C version some how giving off better quality power?

Check attached photos.

And yes I have tested both batteries with drones when freshly fully charged.

David

[NicholasDavid]

A friend of mine has a phantom 3 that one of his batteries gives him weird issues. Like really weird flight behavior. From stability to GPS hover issues. He switches batteries and bingo perfect flight. So maybe

[darkdave]

3s?

[ernstock]

Be interesting to know a bit more - how long have the batteries been in use , have they always performed like this , motor size / props  (...... Current draw ) .
Slight chance it's a shoddy connection on the battery plug.
Possibly the (25/30)c rating (even at 2200mah) is just too low for performance racing multirotors , and maybe one type of battery is handling the strain / voltage sag better.
Tis where a voltage osd comes in handy.

[darkdave]

The poor performing batteries admittedly were not used for about 6 months after I bought them. I have no ata on current draw I havent installed any electronic sensors yet. Are there any in librepilot that I should know about?

[ernstock]

Yeah ,  I just use a simple volts osd ( ' in-line' between camera and VTX )

[darkdave]

I found a voltage/current regulator, should I use this with my poor quality batteries? Question is do I set it to function as a voltage or current regulator?

https://item.taobao.com/item.htm?spm=a230r.1.14.205.JIcquB&id=45628523188&ns=1&abbucket=9#detail

[ernstock]

First off , apologies for delay in reply.
I can't click through to your link , but in my limited experience , no , folk don't seem to use such things , except maybe as s filter for Fpv gear.
Me , I would be putting those iffy batteries to one side - maybe consider using them for something else ( I like to sort the good cells and make 2s batteries for Fatshark goggles ) .
Motor and prop combination info could be used to work a rough guess of amp draw , then a 'C' rating and mah rating  established for the new battery/ batteries. (Also an idea of your flying requirements poss)

[jbarchuk]

The poor performing batteries admittedly were not used for about 6 months after I bought them.

If the batteries had never been charged then they have a very long shelf life. Batteries sit on LHS shelves for months or years and still work fine. I ran into one guy at LHS said he has some lipos that he's been using for 10 years with -proper- charge, discharge, and storage practices. I have a few that at 5 years are perfectly OK.

[RedSun]

Maybe your batteries is very old, bad or damaged, I advise you can  try to change some other batteries like 3s cell lipo batteries, but you should have more check before you change, because if they are go well ,it may waste your time and money.

[chromvis]

sometimes it help to measure internal resistance of each cell. It should be below 60 mOhm, the lower the better.
If there are big difference in IR (internal resistance) between cells, you may have sudden current drops due to electrode surface drainage at sudden high power demand.
Most chargers has IR measurement mode.

[TheOtherCliff]

An old or damaged battery has a lower voltage.  The motors run faster with a newer battery.  If your PIDs are set as high as possible for the old battery (as they should be), it will oscillate with the new battery.  One solution would be to retune with the new battery.  Then the old battery will just act a tiny bit mushy compared to the new battery.  Better yet, have one PID bank set for the old battery and the other for the new battery, but that requires more FMS positions or making changes from the GCS when you switch packs.

Everyone should use a lipo alarm to avoid damaging their batteries. 
Search eBay for
    8s lipo alarm
Sort by price.  They are less than $1.50 each, shipped.  Buy several.    Set them for 3.7v (per cell).  On old batteries you can usually get away with 3.6v per cell because old batteries sag more before being exhausted.