Zippy Flightmax / Turnigy lipo testing

[will_newton]

thank you hobby king for bigger batteries. 8s 5800mah

short rectangle pack: http://www.hobbyking.com/hobbyking/store/uh_viewItem.asp?idProduct=10870
long rectangle pack: http://www.hobbyking.com/hobbyking/store/uh_viewItem.asp?idProduct=10895

now make them even mo' bigger.

 

[evblazer]

Cool! The perfect lightweight pack when I dont' want to lug around my 24v 20ah thunderskies
Course I'll need an 8s lipo charger hm.

 

[Ypedal]

sWeeeet ! 3 of these babies on the 2010 chaos...

 

[will_newton]

there was a post on the HK twitter about these a while back. I was wondering when they would show up. Now where is the 10S version?

 

[SpeedEBikes]

And when will they start stocking 8s and 10s extension cables, y-adapters, etc.? They've had 8s and 10s balance chargers for quite a while but to actually use them for 8s or 10s packs you have to do your own custom cables which is a PITA.

 

[Hyena]

Cool! I notice they've upped the connector size on these to 5.5mm too.
Also they have 4S hard case 4500mah packs now too

http://www.hobbyking.com/hobbyking/store/uh_viewItem.asp?idProduct=10869&aff=81978

keep em coming HK! 6S2P 5000mah hardcase's for under $100 next please

 

[maydaverave]

thank you hobby king for bigger batteries. 8s 5800mah

short rectangle pack: http://www.hobbyking.com/hobbyking/store/uh_viewItem.asp?idProduct=10870
long rectangle pack: http://www.hobbyking.com/hobbyking/store/uh_viewItem.asp?idProduct=10895

now make them even mo' bigger.

Does anyone know if a stock 20 amp infineon controller could handle two of these in series? I think I have read that it has a 60 volt limit.

 

[maydaverave]

Are there two 5 amp+ batteries that would give one around 50 volts nominal, that would be ideal

 

[nomad85]

Are there two 5 amp+ batteries that would give one around 50 volts nominal, that would be ideal

You could get an 8 cell and a 6 cell battery and wire them in series for 51.8v nominal.

 

[Hyena]

I wouldn't run a 16S pack on a stock controller.
They typically run 63v capacitors and your pack 16S pack will come off the charge at 67v.
As Nomad said 14S is a safer bet and running 3 5S packs in series for 15S would be the absolute max, but even that's pushing it to the limit. That said I've done so for over a year with 63v caps and had none blow yet but its the luck of the draw and depends on what components your controller is using

 

[maydaverave]

Thanks for all the advice Like I said I am new to this so I want to start as simple as possible. Two 22 volt packs for 44 volts would offer noticeable improvement over a 36 volt pack, right? Especially a small 7.5 ah pack that I suspect has considerable voltage sag under accelleration. I don't want to push any limits, just a bit mor umph accellerationg and two packs for more range. After I get some experience with lipo under my belt I want to start another more powerfull build. One for fun and one reliable grocery getter. 8)

 

[will_newton]

Thanks for all the advice Like I said I am new to this so I want to start as simple as possible.
-snip-
After I get some experience with lipo under my belt I want to start another more powerfull build. One for fun and one reliable grocery getter. 8)

If i could offer some advice, it would be to not choose a cell count that requires a mix of sizes such 4S and 5S and 6S for a 15S or 6S-6S-5S for 17S.
use 1 size of packs such as 5S only or 6S only giving you 10-12-15-18-20-24S combinations available. You will thank yourself later.

I have plenty of lipo experience, but apparently not enough to keep from hooking crap up wrong from time to time on my mixed pack setup (you can read about it earlier in this thread). I'm am going to have to get some new batteries to fix the problem when I should have done it that way straight off.

just check my sig -11S and 17S- what am I thinking?

 

[GGoodrum]

Now were talking. I've been waiting for more of these 5800-sized packs, and now 8s, which is perfect. I also really like the long format. This makes it much easier for connections, when building packs.

 

[rscamp]

Now were talking. I've been waiting for more of these 5800-sized packs, and now 8s, which is perfect. I also really like the long format. This makes it much easier for connections, when building packs.

Seeing this post reminds me. How is the new BMS coming along, Gary? Spring is coming!

 

[GGoodrum]

Now were talking. I've been waiting for more of these 5800-sized packs, and now 8s, which is perfect. I also really like the long format. This makes it much easier for connections, when building packs.

Seeing this post reminds me. How is the new BMS coming along, Gary? Spring is coming!

I had a long update post last night, but apparently the forum was hacked last night, so my post never made it. I'll do that again this morning. Anyway, we finally had a breakthrough the last couple days. Richard finally found the major problem that has been making my life miserable the last week, or so. It got so bad that I actually looked forward to getting away from the endless testing on Tuesday, to get a root canal.

 

[methods]

This morning I discovered that I ruined 18 x 6S 5000mAh packs

18S 30Ah paper weight

2KWH toasted!
That was all of my ebike packs combined in one shot

I left my cube of doom hooked up with the LED's burning and the CA attached.
Between the 70mA of the CA and the LED current I drained an 18S pack down to 34V over a few days.

I figure the cells sat for 24 - 48 hours at between 1.5V and 2V
I am sure I can charge them back up but they are trashed. Half of those were brand new with less than 10 cycles on them.

It was 100% my fault - my charger overheated due to a crappy fan (that I installed) and went into safety mode after only putting a couple AH into the pack - then it sat for a week.

Let that be a lesson to you NoObs -> Dont EVER leave your packs in a state other than fully charged or (3.7V charged) and dont EVER leave any type of device plugged into the packs that could trickle them down. Even if you think it is on a charger.

* Controller - 60ma
* CA - 70mA
* BMS - varies
* Cell Display Device - varies

Any of those things will drain your pack dead in days.

Hell - I was running a 30Ah pack which you would think could handle a trickle for a LONG TIME -> but when you do the math.... It does not take long at all.

-methods

 

[nomad85]

This morning I discovered that I ruined 18 x 6S 5000mAh packs

I'm sorry for your loss

 

[vanilla ice]

Oh man that sucks. Definitely a good lesson for everybody. I've done the same thing before but to a much lesser pack. I relied on the controller's auto ignition shutoff when charging, but the charger burned out. And the bike drained for two weeks. Now I unplug the pack from the bike to charge.

 

[steveo]

This morning I discovered that I ruined 18 x 6S 5000mAh packs

18S 30Ah paper weight

2KWH toasted!
That was all of my ebike packs combined in one shot

I left my cube of doom hooked up with the LED's burning and the CA attached.
Between the 70mA of the CA and the LED current I drained an 18S pack down to 34V over a few days.

I figure the cells sat for 24 - 48 hours at between 1.5V and 2V
I am sure I can charge them back up but they are trashed. Half of those were brand new with less than 10 cycles on them.

It was 100% my fault - my charger overheated due to a crappy fan (that I installed) and went into safety mode after only putting a couple AH into the pack - then it sat for a week.

Let that be a lesson to you NoObs -> Dont EVER leave your packs in a state other than fully charged or (3.7V charged) and dont EVER leave any type of device plugged into the packs that could trickle them down. Even if you think it is on a charger.

* Controller - 60ma
* CA - 70mA
* BMS - varies
* Cell Display Device - varies

Any of those things will drain your pack dead in days.

Hell - I was running a 30Ah pack which you would think could handle a trickle for a LONG TIME -> but when you do the math.... It does not take long at all.

-methods

This is against all lipo rules....

if they are not totally flat .. say around 1.5v+ each cell... i would charge the pack at about 1/2 amp charge rate to bring it to 3v & then charge it up normally

i would test capacity & resistance of each pack to ensure there is no damage to the packs .. you may be lucky!

i've had lipo cells from 1-2v test at full capasity & resistance

again .. this is what i would do .. not saying its the right thing to do... lol

-steveo

 

[Hyena]

Daaaaamn Methy, that sucks dude.
I was ghetto balancing an old pack that had one high cell a while back with a fat 5 ohm resistor and got distracted with something else and accidently forgot about it. Half a day later I remembered and ran back to it but luckily it had only discharged that cell to 3.3v so I just topped it back up and it was fine.

You need to speak to someone who can make a good lipo BMS

Take note n00bs, if Methods can do something like this it can certainly happen to you.

I'm a bit like you methods, I've become complacent with my lipos because they're so well behaved in charging, discharging and maintaining balance. One of these days it's going to bite me on the arse though :? But until that day...

 

[methods]

I just brought all the packs in.
I am going to charge them up with the iCharger then discharge them into my 10Kw discharge station (aka Ebike )

I am guessing that I will get a fair amount of capacity back (maybe 80%) and - given the large size of my packs - enough C rating to handle the type of riding I do.
My 15Ah 24S pack is rated for 300A continuous so if the C rating drops by 75% down to 5C I would still be good for 45A continuous - which is good enough for most ebike applications.

Will report back.

-methods

 

[rscamp]

Let that be a lesson to you NoObs ->
-methods

That'll teach us!

Wow.

 

[methods]

That'll teach us!

Wow.

Looks like I am the nOoB today eh?

Fine with me - so long as I dont do the same thing to my 20S 48P pack


-methods

 

[Hyena]

my 20S 48P pack

 

[methods]

For what it is worth I recovered the batteries.

I built up a 15Ah 24S pack and put it on my trike with the current limit set to 120A
I noticed no change in performance - so far I have burned through 7Ah.

I have never discharged the pack to LVC so I dont really have a point of reference - but from what I see it appears that the AH vs Volts way-points as normal. The V under load also seems not to have changed. I will run 12Ah out of it and if it is still good I am calling it a 100% recovery.

I will build up some of the other cells into 12S 10Ah packs to see how they perform.

So - I guess some times we get lucky.
I have the feeling that slowly bleeding them down is not as destructive as hammering them into the ground at 20C.

I also took Luke's advice and very, very slowly charged them back up. Literally took days

-methods