Reminder: Don't trust Hobbyking batteries.

Arkz

10 mW
Joined
Jan 29, 2013
Messages
32
Location
England
I've been using the same set of LiPos on my bike for a few years. Can't go very far with em. So last November I spent £160 on some more batteries to supplement what I already have. Another 2x 5s batteries and a 3s battery. Was good, increased range, could go on longer rides.

Would check the balance now n again n do a balance charge when they needed it. Don't use the bike that often in the colder months but been using it more recently.
Noticed a few weeks ago that the voltages seem a little off after a ride. So grabbed me balance checker and connected to each battery, to see if they're alright. Fully charged and unused should be 4.2V per cell obviously.

So I'm checking me old ones. all around 4.18v-4.21v. About right, don't wanna over charge LiPos obviously, it's why I keep them in fire retardant bags. So after checking the old ones I check the new ones. And wouldn't ya know, something's not right.

So I'm checking the new ones, should also be about 4.2V for each cell obviously.

4.56V, 4.55V, 4.57V and so on. And I'm like... Oh shit!! That's way over. Turns out all of the new batteries were overcharged, except c2 on one of the 5s packs. That was 0.00V... It's gone completely bad in that short time and is shorted, it's just passing the power through. Result being when they get charged it's bypassing that cell and giving all the others too much. This will have been happening each time I charge my bike. I'm shocked they hadn't burst into flames. They were all swollen and under high pressure. I've since drained them all. But bloody hell. That's what I get for not checking the balance every time.

Even the old set I'm still using are Zippy (Hobbyking). They claim to be 30c constant, so at their rated capacity- 150A. Which I don't believe for a second anyway. But get this, I'm only drawing about 30A peak and after a ride they're pretty damn warm. Dodgy much?

Anyway enjoy some pics of one of the 5s's

dZizyp8.jpg



Given the pressure I thought it best to cut them out of the blue shrink wrap. Put a little cut in the lip of it and began to gently tear it open, till the pressure started the push the tear along its self and burst out of the shrink wrap. Giving me a mini heart attack in the process.

gbJ6Mhp.jpg


I've had Turnigy (Also Hobby King made) go puffy as well. And a brand new 5s Zippy pack a few years ago, charged to 4.2v per cell and left on a shelf to be cycled a few times, randomly cook the 3rd cell. Came out to garage next day and it was melted down to desk, middle cell had cooked its self to burnt flakes, melted the shrink wrap and stuck its self down. Having never even being used. They even tried to argue the warranty with me saying I must have damaged it. Having already explained that the only thing I did was top it up to 4.2v p/cell. Ugh..

I'm sick of wasting money on this crap and don't exactly have much to spare. Does anyone know a UK based, or at least Europe based seller that I can buy good quality LiPo's from for a decent price? Or maybe LiFePO4's? At least when they went bad that was it. No fire risks.
 
Glad to hear there was no fire.

With new Lipos the balance needs to be checked every cycle until we are certain they are behaving correctly. Use Balance charging the first few cycles, and monitor the voltages before and after charging until they have developed a perfect track record. There should be no surprises here. If a cell is zero volts don't charge the brick. Should be no overcharging if we are checking before charge. If they behave perfectly for 10 balance charging cycles, then bulk charge, but check cell voltages before and after every time. After 10 cycles of checking voltages before and after every bulk charge cycle then one can check less often, but continue to check weekly or so.

The chemistry is getting better with regard to not going up in smoke when slightly overcharged. That has certainly saved you from a fire.

The low prices and good performance are nice, but RC battery quality is not perfect. They can suffer from manufacturing problems or shipment damage. So it is our job to do the Quality Assurance and retire or repair the occasional bad brick. I would assume this with any RC lipo, not just Hobbyking. Check and re-check. We are the BMS.

My own experience has been that Zippy has been slightly more problematic than Turnigy. My Zippy LiFePO4 has 100% swelled (even though they seem to still work). The LiFePO4 is much lower in current capacity as well, so a larger pack is needed to handle the current. I would not use them for ebikes (they are good for 12V applications in 4S). I balance charge them every time.

I've had excellent results from Turnigy except when I make a mistake and run them to zero. My fault, pay for new ones, then re-verify them carefully.

It is well known that the manufacturer's peak ratings are too high for ebike use. Divide by four for a starting point. If they warm up, reduce further. RC applications generally have huge airflow and don't mind a little heat.

For LiFePO4 I've heard Ping is pretty good, I have not tried them. Expect more bulk and weight of course.

Monitor any non-BMS equipped pack closely, that's our job. As they say, Trust but only after Verify. We are the BMS.

Or get BMS protected packs. You might try the 14S 54V Tool packs.

Stay Safe.
 
" So I'm checking me old ones. all around 4.18v-4.21v. "

Was that after they have been sitting for a day or more ?

What charger do you have ?

What voltage per cell are you charging them to ?

With My little 150 watt and 120 watt chargers I am charging to about 4.15-4.18 volts per cell, with a difference of around .04 , max difference between each cell. On the two new Turnigy's it showed .05 max difference with only one charge cycle so far.
( otherwise Zippy's 6s and 7s 35 c discharge rating packs for a couple of years now)
After they sit for even a minute or more off the charger they read about 4.10-4.14 per cell.
So I am wondering if it is your charger that is doing the damage ? ( except for the one with the one bad cell )

I am charging and sometime balance charging at around 1c-1.2c since the little chargers do not charge more than that because the packs are 6 and 7 cells
I Just got 2 turnigy " Higher Duty Series " , higher c rating 7 s packs ( 60 c Discharge and 5c Charge Rate ) , only one cycle on them right now, and ordered a much larger charger so I will be charging at a higher c rate, like up to 2c unless I use the new parallel balance wire harness I also just ordered. then I will be charging at 1c or less since there will be two batteries charging at the same time.

I often do not ride for a couple of days with the packs charged to about 89-90 % and the Zippy's still seem to be working fine, so much so that I am now just charging , not on balance mode, and they all come out to be .04 off max between the cells . And never felt them warm, although I do not go to full 30-35 amp draw for any long period of time, only up to a couple of minutes before backing off the throttle and cruising at around 20 amps or even less for a few seconds or minutes .

So Wondering how long you are pulling 30 amps out of them for on a ride, and what amps are you charging them at ?

Also Chargers are known to sometimes not be calibrated, I would love to see a good thread on how to calibrate our hobby / lipo battery chargers .

I am thinking about only buying higher c discharge rating batteries in the future like the new Turnigy's I just bought.

I Just do not have the money for the newer Graphine Packs, but if you do perhaps that is what you should only buy for all your new pack buy's ?
 
That's why I always balance charge lipos, I built a 1kwh 16s2p pack out of multistars used it for a year checked it over and one of the parallel cells had gone bad and then forced it's neighbour to pick up the slack.

I took them apart and measured the IR and voltage the bad cell had reached 1ohm and fell to 2v when seperated and the neighbour had got to 0.2ohm from being abused when it's mate fell over but held its voltage at 3.4v still 0.2v below the pack average but even my worst puffed cell is fine compared to yours that's so close to a thermal runaway it's unreal your lucky go buy a lotto ticket !.

The healthy cells where in the 25-40 milliohm range and didn't rise so fast during charge, they still had around 90% dod so I resembled them into a 8s3p pack for a small razor scooter that should have some good range.

Morral of the story always balance charge or use a bms, I don't like basic bms I can not monitor what the individual voltages are so use a bluetooth one that you can see what is going on but I've not seen them measure IR either so I have a good Rc charger that can measure IR and balance charge upto 10s and then charge the pack in half's or what ever suits my needs i done two sets of 8s to get my 16s pack then monitor discharge with a watthour gauge or at least as volt and amp meter to monitor sag.

You will catch a fault on the charge cycle then the most dangerous time, naked bulk charging is dangerous and needs to be monitored in some way to protect yourself from what happened.

Below is a picture of the two cells that took the plunge next to a healthy one, through good maintenance they were caught well within time and the rest of the pack can live on to fight another day, as you can see for 1ohm there's not much swelling so relying on visual when it's wrapped in shrink won't do.

View attachment 1
 
ScooterMan101 said:
I am thinking about only buying higher c discharge rating batteries in the future like the new Turnigy's I just bought.

I Just do not have the money for the newer Graphine Packs, but if you do perhaps that is what you should only buy for all your new pack buy's ?

I've got the 10ah 4s graphine packs i got 6 of them for 24s worth and over a year and half I've not got any bad cells all have exceptionally low IR I do have 3 cells that will drop a bit behind the others so they need a good balance charge over time when I received them one cell was .2v behind the rest and I haggled another pack ( no easy feat ) but it's managed to hold up over time just got to keep an eye on them every month if not in use put them on a balance charge to 3.9v cycle them, the discharge is to be believed they hold high and push hard good pack for the weight bit large though.
 
Some balance chargers will imbalance the pack when a cell drops to zero. It is best to use a charger that doesn't have this flaw. The BC168 type chargers have a separate circuit per cell group and charges each group independently, so it CANNOT overcharge a cell group.

Most chargers are really bulk chargers with cell monitoring and balancing. These often have flaws in their firmware that allow bad things to happen when the circumstances are just right. Even expensive chargers can behave this way, I recently had a Cellpro do this on a 10S pack that had a cell group fail to zero. It overcharged the other cell groups. It works perfectly until one cell group goes to zero, then it misbehaved. Buggy firmware, apparently.
 
Ichargers are good for detecting hic ups I've been using the 1010b+ can't fault it in balance mode, In bulk charge mode it just asks is it a 9s or 10s pack for example if a 10s pack gets down to below 9s full charge state it will ask are you sure it's a 10s pack so the end voltage doesn't blast past into meltdown if it was a 9s, theres also a temp probe so it monitors internal and external temps and cuts out at set values that gives me piece of mind that it will cut out before things get nasty.
 
I have a fun story for you all.
I was a long time advocate of rc lipo.. and spent a lot of time educating people on how to not blow their homes up here..

So the sales manager at hobbyking puts up a thread and is looking for multistar product reviewers.. i sign up to get 2.
Two puffing, misbalanced packs show up at my door... poorly packed and obviously damaged during shipping.

Since they shipped me free stuff, i just didn't do a review.
I put both of them in ammo cases outside of my house on concrete, and one started leaking..
I ended up discharging them and sending them to a recycler.

And that was the end of me owning and advocating for the use of RC Lipos. If they can't ship an influential person a working pair of batteries, what the hell are they shipping everyone else?
 
Good reminder, though I would expand it to all RC Lipo, not just Hobbyking

I've had good luck with Turnigy, and a few premature failures with Zippy, but I'm pretty sure it's mostly down to luck.
 
This small 6s tenergy checker would be good to use especially when charging, it actually will set off a loud alarm if a cell voltage reaches 4.22. Would only be useful if your within range to hear the alarm. Cost is 10 dollars but they work good, its cheap insurance.

As far as lifepo4 being safer, from my expierence they are not. I shorted out one of the A123 26650 cells, and that short punched a hole on the cell and it caught on fire. The fire was as violent as any li-ion fire I have seen. I see many lifepo4 in pouches, so they are out there.

I balance charge everytime, when not balance charging I use the below alarm and just keep close eye on the battery pack. I don't trust the bms or charger to be reliable 100 percent of the time, the day I don't monitor it is the day they will fail. After experiencing my lifepo4 fire I been even more careful. Lithium is safe it just takes one time that you get complacent and it will cause problems.

tenergy checker.jpg
 
Dear Clueless)(OP),
I mean really, doesn't everybody know YOU DO NOT STORE LIPOLY AT FULL CHARGE!
He(and I'm starting to think he is a Troll since he hasn't come back)doesn't tell us what charger he is using, but the Hypereon and Thunder balance chargers I've used, won't allow the following
....It's[the battery] gone completely bad in that short time and is shorted, it's just passing the power through. Result being when they get charged it's bypassing that cell and giving all the others too much. This will have been happening each time I charge my bike.
The guy killed his batteries by being cocky when he didn't understand the first rule in charging LiPoly.
I've been using Zippy, Turnigy and now Multistar for years and I had one brick get puffy(a Zippy)about 5 years ago and HK replaced it. That's it, one puffy brick in 7 years.
 
ScooterMan101 said:
" So I'm checking me old ones. all around 4.18v-4.21v. "

Was that after they have been sitting for a day or more ?

What charger do you have ?

What voltage per cell are you charging them to ?

With My little 150 watt and 120 watt chargers I am charging to about 4.15-4.18 volts per cell, with a difference of around .04 , max difference between each cell. On the two new Turnigy's it showed .05 max difference with only one charge cycle so far.
( otherwise Zippy's 6s and 7s 35 c discharge rating packs for a couple of years now)
After they sit for even a minute or more off the charger they read about 4.10-4.14 per cell.
So I am wondering if it is your charger that is doing the damage ? ( except for the one with the one bad cell )

I am charging and sometime balance charging at around 1c-1.2c since the little chargers do not charge more than that because the packs are 6 and 7 cells
I Just got 2 turnigy " Higher Duty Series " , higher c rating 7 s packs ( 60 c Discharge and 5c Charge Rate ) , only one cycle on them right now, and ordered a much larger charger so I will be charging at a higher c rate, like up to 2c unless I use the new parallel balance wire harness I also just ordered. then I will be charging at 1c or less since there will be two batteries charging at the same time.

I often do not ride for a couple of days with the packs charged to about 89-90 % and the Zippy's still seem to be working fine, so much so that I am now just charging , not on balance mode, and they all come out to be .04 off max between the cells . And never felt them warm, although I do not go to full 30-35 amp draw for any long period of time, only up to a couple of minutes before backing off the throttle and cruising at around 20 amps or even less for a few seconds or minutes .

So Wondering how long you are pulling 30 amps out of them for on a ride, and what amps are you charging them at ?

Also Chargers are known to sometimes not be calibrated, I would love to see a good thread on how to calibrate our hobby / lipo battery chargers .

I am thinking about only buying higher c discharge rating batteries in the future like the new Turnigy's I just bought.

I Just do not have the money for the newer Graphine Packs, but if you do perhaps that is what you should only buy for all your new pack buy's ?

That was fresh off the charger. I use Turnigy 6s chargers for doing balance charges, I believe they're clones of the IMAX B6. And a 54.6v 13s 2A generic charger for charging them as a pack on the bike. When I balance charge them I charge to 4.2v per cell as is standard.

Only time I'm pulling 30A constant is going up a steep hill. I don't always ride fast anyway so a lot of the time I'm probably pulling about 15A. Just as a precaution I've set the current limit of the controller to /2. I don't mind it being weaker if it's gonna preserve my cells. Problem is battery prices seem to be higher than ever, with the weaker pound.
 
motomech said:
Dear Clueless)(OP),
I mean really, doesn't everybody know YOU DO NOT STORE LIPOLY AT FULL CHARGE!
He(and I'm starting to think he is a Troll since he hasn't come back)doesn't tell us what charger he is using, but the Hypereon and Thunder balance chargers I've used, won't allow the following
....It's[the battery] gone completely bad in that short time and is shorted, it's just passing the power through. Result being when they get charged it's bypassing that cell and giving all the others too much. This will have been happening each time I charge my bike.
The guy killed his batteries by being cocky when he didn't understand the first rule in charging LiPoly.
I've been using Zippy, Turnigy and now Multistar for years and I had one brick get puffy(a Zippy)about 5 years ago and HK replaced it. That's it, one puffy brick in 7 years.

Dear arrogant person. Are you suggesting I don't charge my batteries before a ride? I at no point said I leave them fully charged for long periods of time. I tend to leave ones I'm not using at about 60%. If they're being used of course I'm going to fully charge them. And even then fully charging it isn't going to cause a problem unless it's left for a while. I've charged them cause I'm going for a ride.

I'm not being cocky at all. They should be built well enough that they don't need a balance charge every single time. I usually go about 10 charges in series before doing a balance charge of each pack separately. I usually check the balance often too. This was simply a period of me using the bike nearly every day for a few weeks, and between the last balance charge and this one, this happening.

Nice to see this site still has moody people like you, who like to lash out at others.
 
Stop using pouches unless you have a proper compression housing for them.
If you dont have a compression housing: 18650 cells.

/thread.
 
neptronix said:
I have a fun story for you all.
I was a long time advocate of rc lipo.. and spent a lot of time educating people on how to not blow their homes up here..

So the sales manager at hobbyking puts up a thread and is looking for multistar product reviewers.. i sign up to get 2.
Two puffing, misbalanced packs show up at my door... poorly packed and obviously damaged during shipping.

Since they shipped me free stuff, i just didn't do a review.
I put both of them in ammo cases outside of my house on concrete, and one started leaking..
I ended up discharging them and sending them to a recycler.

And that was the end of me owning and advocating for the use of RC Lipos. If they can't ship an influential person a working pair of batteries, what the hell are they shipping everyone else?

Great story.

So essentially a poor pack job by the kid at the shipping desk, or bad performance of the shipping company (which is not uncommon, they can break almost anything) soured you on lipo?

Regarding chargers and pack problems, many behave fine until a cell goes to zero or dramatically out of balance. Then they don't. They handle mild unbalance ok, but not serious unbalances. They overcharge some cells trying to balance the pack. This is not safe.

Even the best chargers can have flaws in their firmware, or can fail electronically without warning. When a cell (group) voltage drops the charger should not continue, period. Changing to one less cell and continuing the charge to a lower voltage is NOT safe. The cell must be physically removed from the pack so there is no current flowing through it.

It does not matter what type of cell it is, pouch, 18650, whatever. Bad cells must be physically removed (replaced) for a safe pack, or the whole pack retired for safety.
 
I had also problems with puffing of Hobbyking Zippy "Lipoly" pouches. The most problematic for me was the low C-rate packs 10-15C. I bought 5 packs about 4 years ago and all of them started to puff only when they were lying in the shelf at 3.6V volts.

Little offtopic: recently I got some free channels on my battery testers and so I started with cycle life test of pouch batteries. I started tests of Turnigy Multistar 5200mAh 10C and Turnigy Graphene 1000mAh 65C, both 4s packs. I have dissasembled the packs to single cells and use 4-wire clamp connection for each cell to tester. So the cells are not compressed during testing.

My initial test setting was: 1C charge - 1C discharge, 100 % DoD (4.2V - 3V range) with 100mA charging cutt-off current and 10 min rest time between each chg and dchg. Each 50th cycle is inserted a nominal capacity test with 0.2C discharge rate.

I have now 450 cycles with sample of Mutistar 5200mAh cell and so far I am very satisfied with its performance. The initial nominal cycle was 5566mAh and 450th nominal cycle was 5463mAh so only 2% capacity fade and still 250mAh above manufacturer capacity rating! No puffing so far. (I'm sorry but I can not show graphs in public yet :( )

This totally outperform almost all 18650 cells even High Power ones like LG HG2 under this particular 1C-1C test. It should be noted that for 18650 cells is manufacturer recomended standard charging rate 0.5C and so most 18650 cells suffer under 1C charge rate.
 
Pajda said:
I had also problems with puffing of Turnigy Zippy "Lipoly" pouches. The most problematic for me was the low C-rate packs 10-15C. I bought 5 packs about 4 years ago and all of them started to puff only when they were lying in the shelf at 3.6V volts.

Little offtopic: recently I got some free channels on my battery testers and so I started with cycle life test of pouch batteries. I started tests of Turnigy Multistar 5200mAh 10C and Turnigy Graphene 1000mAh 65C, both 4s packs. I have dissasembled the packs to single cells and use 4-wire clamp connection for each cell to tester. So the cells are not compressed during testing.

My initial test setting was: 1C charge - 1C discharge, 100 % DoD (4.2V - 3V range) with 100mA charging cutt-off current and 10 min rest time between each chg and dchg. Each 50th cycle is inserted a nominal capacity test with 0.2C discharge rate.

I have now 450 cycles with sample of Mutistar 5200mAh cell and so far I am very satisfied with its performance. The initial nominal cycle was 5566 mAh and 450th nominal cycle was 5463mAh so only 2% capacity fade and still 250mAh above manufacturer capacity rating! No puffing so far. (I'm sorry but I can not show graphs in public yet :( )

This totally outperform almost all 18650 cells even High Power ones like LG HG2 under this particular 1C-1C test. It should be noted that for 18650 cells is manufacturer recomended standard charging rate 0.5C and so most 18650 cells suffer under 1C charge rate.

It would be good to see a separate thread on your testing, excellent info. Can you constrain the cells with something simple to avoid any issues caused by lack of compression?
 
you would need stiff aluminium plates (4~5mm thick) on both ends and bolts to keep everything compressed. preferably also 1~2mm aluminium between each pouch to prevent any "exitement" from spreading and spread the forces around the cells more.

in cars they use metal cooling plates between the pouches for and big ass heavy glassfiber reenforced nylon and metal endplates to keep everything together.
 
Icecube47 did a lot of reviews on HobbyKing Lipos, you can search his results easily.
He states there is a 10-15% failure rate on the Lipos he had recieved. That was a year or two ago.
He did extensive testing when he receives his.
He has couple of the really expensive balance chargers, and documented very well on video.

I like 18650's and will stick with them, whether it be tool battery packs or custom made.
 
Yes, the influence of compression of commonly used pouch cells (Multistar) for DYI is also interesting topic to test. But now I am thinking about issue tied with this thread topic which is safety during the tests. I have prepared tester for high C-rate test of this 5200mAh 10C Multistar cells. I can test up to 40A discharge, which is about 7.5C. I made initial 40A dchg test with one cell sample (without any compression) and the cell perform well with 5.437mAh capacity and ended at 70°C with no visible puffing.

But simply do not have the balls to leave it running unattended. I think that "Lipo safety bag" can help with this but there will be definitely problem with heat inside the bag. Do you have any idea how to deal with this? The ammo case on concrete sounds good. :)
 
Not only don't trust them, don't waste your money on them or any other RC type lipo. They just aren't worth the risk of life. Look how many fires experienced users have had. It's quite likely that we've lost one or more forum members to fires and never even heard about it. The only way to use them reasonably safely is to store and charge them outside where if they flame out the fire can do no damage other than to the bike.

7 years ago I had a brand new unused pack that was perfectly balanced upon arrival flame out after sitting untouched for a month. Thank goodness only one cell flamed out and it was the top one and the 20 new packs spread sufficiently apart that it didn't start a chain reaction of all the packs.

Here's the aftermath of just the top cell in that 4s5ah pack:
View attachment 3
Burst Lipo B.JPG
Burst Lipo C.JPG
Burst Lipo D.JPG
 
and people still call me out for having poor business practices for refusing to work with pouches.... :roll:
 
flippy said:
and people still call me out for having poor business practices for refusing to work with pouches.... :roll:

Dell and Sony laptops that caught fire were using 18650s.

Tesla that use 21700s have more fires per 1000 cars than Nissan Leafs despite using prismatics, because Nissan Leaf cells use proper compression.

There is nothing "special" about canister style batteries, except that they come already compressed. If you know what you're doing pouches have similar risk. It's only if you don't know what you're doing, that they are unsafe.
 
Everyone saying compression is the answer, surely if they try to swell under compression they will burst open and vent. Or worse due to being pressed together, should one set fire it's gonna pass straight to the next cells.

Seems like there's no good single type of battery. I used to run a 36v LFP that was 12s18p. Lasted a good while, but with 18650s you have the issue of getting bad cells soldered together with the others. When doing maintenance on that I discovered a few had cooked and blown the nickel weld off the tab. Also didn't help that the useless Chinese manufacturer hadn't built the pack right. (1s and 12s didn't have the cross strips of nickel on the rows of batteries in them, making them both 9p instead. With 2s-11s being 18p. Clever right?

Years and years ago using AGM's sucked. Big heavy things with poor power density and rubbish cycle life. But at least none of them ever burnt or swelled.
 
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