Need a replacement for my Ping

[snowranger]

My Ping has finally bit the dust at just over 5000 miles. There are definitely at least two bad cell groups maybe more. I might try to salvage some of the battery at a future point, but I need a reliable battery now. I am looking for 20 ah with maximum draws of 25 amps. What I am looking for is reliability and ease of cell replacement if necessary. No more nasty solder surgeries or cutting PCB tab connectors for me That rules out another Ping.

My first thought is to get a prebuilt headway pack. If the bms is bad, could I swap my Ping bms into the pack? Are they compatible? Also 38120 replacement cells would be readily available in the US.

Any recommendations out there for good value and reliable Seller? Thanks.

 

[recumbent]

How about four, 8s, 25c, 5.8 ah lipo's, parralleled to make 60 volts and 12 ah from Hobbyking for $99ea?

I just received my 4 packs and they were all perfectly balanced (3.88v ea) up to 31 volts per pack.

They are HALF the size of my lifepo4 pack with only 10 ah at 10c rating.

The high "c" rating is more of a bonus than most may think. When you accelerate at a stop light the voltage sag is minimal, which translates to noticably less wide open throttle settings and seemingly further range.

I love these battaeries so far but only had them for a day

 

[dogman dan]

Fortunately my first ping has no problems still, with more than 5000 miles. But cell replacement on it would be a real pain compared to headways.

I can't see any reason why your old ping bms wouldn't work with headway cells for discharge rates similar to the old ping.

Lipo would require you to get a new charger, and you would lose the convenience of just plugging in once and riding later. But the discharge rates, and ability to add packs for more capacity, or carry less for a short ride is pretty nice. Smaller physical size is nice too.

The third option would be 20 ah A123 pouches.

 

[Ykick]

Most prebuilt headway packs have been discontinued based on recent communication with several vendors. If you go headway you're pretty much stuck building it yourself which is what I'm currently gearing-up to do. Luckily, there's great pack building info to be found for Headway cells.

I've also heard/read the Ping BMS should work with headway - I was looking at buying an older version from him but I dunno what BMS, if any, I'll use yet? I may just go bareback and monitor closely with cell logs? I don't plan to use max capacity from my pack so I might be okay? 16S, dunno? Maybe charge 4S or 8S at a time? At least the headway cells are more readily replaceable if/when the need arises?

Good luck and check ev components for loose cells and building blocks - they got great prices and good support.

 

[snowranger]

My concern about using the Ping BMS is that you need to take each cell to 3.75 volts rather than the 3.65 specified by Headway.

 

[Ykick]

My concern about using the Ping BMS is that you need to take each cell to 3.75 volts rather than the 3.65 specified by Headway.

I did not know that about Ping and I thank you for pointing that out. With so many details in all of this technology and confusion - it's a full-time job keeping up with every little thing. I'm very grateful for this place and what little time I have to read I always learn something new and often important!

best to you and your pack search...

 

[snowranger]

How about four, 8s, 25c, 5.8 ah lipo's, parralleled to make 60 volts and 12 ah from Hobbyking for $99ea?

I just received my 4 packs and they were all perfectly balanced (3.88v ea) up to 31 volts per pack.

They are HALF the size of my lifepo4 pack with only 10 ah at 10c rating.

The high "c" rating is more of a bonus than most may think. When you accelerate at a stop light the voltage sag is minimal, which translates to noticably less wide open throttle settings and seemingly further range.

I love these battaeries so far but only had them for a day

At full charge, will this setup blow up my watts up meter and controller?

What about 12s instead? Would that be slower than 16s lifepo4?

 

[dogman dan]

I didn't realize, or had forgot that the headway 16s charged to 58v, while the pings charge to 60 v. So If you did use a ping bms, maybe the thing to do would be to get a charger that shuts off at 58v. Then you could only occasionally balance the pack at 60v. Or just balance with a 3.65v charger every two months or so. If you need to balance more often than that, you are flogging those batteries anyway, so just charge em to 60.

Would it really damage the headways that much to go to 3.75 once, or once in a while? I know 4v would be bad, but would 3.75 ruin headways, or just reduce cycle life perhaps. In any case, if you used the ping bms at 58v, you'd miss out on balancing but still have the lvc when you need it. Used nice, say 3c discharge rate to 80%, they should stay balanced enough for a fairly long time.

And the other option, cellmans A123's, Could they be charged to 3.75v?

 

[ebikes-sf]

I'm facing a dilemma with battery packs. I'm looking to buy packs in quantity to include with BMC kits I'm offering but compact LiFePO4 packs do not last as long as they could if they were constructed better - they're usually composed of soft shell cells stacked next to each other (like ping packs), that's what makes them compact. There are at least 3 issues I see with that:
1. No space for cooling. Cells in the middle run hotter than cells on the outside which may prematurely reduce lifetime of inner cells.
2. Not enough physical protection between cells against shocks and vibration.
3. They are hard troubleshoot and repair.

On the other hand, while packs composed of hard shell cells (headway) don’t have the above issues, they're larger in size, heavier, and not so attractive for smaller bikes (ok for cargo bikes).

LiPo packs look attractive because of very high density and high discharge rates, but they're hazardous, if overcharge protection circuit fails, they catch on fire. Also, they about 1/3 of a lifetime of LiFePO4.

If anyone can recommend good pack distributors, or interested in a group buy (I can orginize it and come up with initial investment), please let me know.

ilia

 

[swbluto]

A123 flatcells have pretty high discharge current capability, while also having compactness, so a 500 wh pack for anything less than 3000 watts would surely not have "over-heating" concerns. And, if it gets upto 110 degrees (boohoo), you're only looking at 2500 cycles instead of 4000.

 

[ebikes-sf]

A123 flatcells have pretty high discharge current capability, while also having compactness, so a 500 wh pack for anything less than 3000 watts would surely not have "over-heating" concerns. And, if it gets upto 110 degrees (boohoo), you're only looking at 2500 cycles instead of 4000.

Yes, I heard those are great cells. I been trying to get in touch with A123 but they only want to deal with large dealers/ev manufacturers. Any leads where these can be obtained?

Thanks!

 

[snowranger]

I am pretty sure my Ping died from vibration and shock rather than heat. All bad cell groups were at the ends of the pack, and there were obvious signs of fluid leakage at the bottom of the pack.

Even if you use A123 prismatic, you have to protect them some how.

Has anyone had any luck getting a hold of Victoria recently? Edit- well nix the Victoria idea. The MOQ is 10 packs.

 

[dogman dan]

Yeah, it's why I make the really tight fitting custom box for my pings. All the movement and rubbing that goes on in the battery box is between the inner box and the outer toolbox. It's amazing how much wear shows on the corners and bottom of the inner box. The inner box fits so snug that there is no rubbing at all on the actual battery. Even if you stay on pavement, a battery gets rattled quite a bit.

 

[mr.electric]

I agree that the current soft cell packs are too fragile. I have been thinking of a custom made metal case. It would be a piece of rectangular aluminum tubing sligthly larger than the pack that has foam strips along the length to keep the battery from bouncing while still letting air flow past the pack. One end cap would have a fan the other holes for the air to escape.
I wish I could get A123 flat cells!! (or round ones )

 

[snowranger]

Got a quote from cell_man. Now awaiting a quote from Michelle. She says she has some Headway packs. Anyone done business with Michelle?

 

[dogman dan]

My first ping, I was worried about it getting too hot. So I made the protective box by taking an aluminum cookie sheet and folding it around the pack. Cut some pieces out at the corners, leaving just enough to fold a corner, and wrap a tab around the corner. The end result is a very very tight fitting custom box covering 5 of 6 sdes of the battery. Both my batteries have survived end over end crashes in such a protective case, and some padding between it and the outer metal toolbox. The cookie sheet makes a good heat sink, too good in winter, so I used plastic sheeting on the second one. I posted pix a few months ago, showing how I made the plastic box. In battery section.

 

[mr.electric]

I really like the hi-powered cycles battery pack and 6 amp charger. It is compact and seems to work very well so far.I have only got a few cycles though.
http://www.hi-powercycles.com/product.sc?productId=12&categoryId=5
The 6 amp charger seems to charge my 10 ah pack in less than an hour after most in town rides. I have never monitored how long it takes to charge from totally empty but it seemed like just an hour or two.
It has a separate charge and discharge plug. The charger only has two wires and there are no switches or controls on the charger. You just plug the two together and the charger fan starts. At the very end of the charge cycle the charger fan pulses a few times then turns off for good.

 

[snowranger]

I really like the hi-powered cycles battery pack and 6 amp charger. It is compact and seems to work very well so far.I have only got a few cycles though.
http://www.hi-powercycles.com/product.sc?productId=12&categoryId=5
The 6 amp charger seems to charge my 10 ah pack in less than an hour after most in town rides. I have never monitored how long it takes to charge from totally empty but it seemed like just an hour or two.
It has a separate charge and discharge plug. The charger only has two wires and there are no switches or controls on the charger. You just plug the two together and the charger fan starts. At the very end of the charge cycle the charger fan pulses a few times then turns off for good.

Too rich for my blood.

I just received a quote from Michelle for the 48V 20ah Headway Pack and charger, $530 + $144 shipping. Hope she is legitimate.

 

[evblazer]

I just received a quote from Michelle for the 48V 20ah Headway Pack and charger, $530 + $144 shipping. Hope she is legitimate.

That price looks pretty good I think if you compare it to what loose cells cost. $19x30 (or 32?) is around $600 then you need holders and busbars. I wonder if they are tabbed or threaded cells.

 

[MitchJi]

Hi,
Hi,

Would it really damage the headways that much to go to 3.75 once, or once in a while? I know 4v would be bad, but would 3.75 ruin headways, or just reduce cycle life perhaps. In any case, if you used the ping bms at 58v, you'd miss out on balancing but still have the lvc when you need it. Used nice, say 3c discharge rate to 80%, they should stay balanced enough for a fairly long time.

And the other option, cellmans A123's, Could they be charged to 3.75v?

A good way to increase the life of LiFePO is to limit the charge to 3.6v or 3.65v. More info here:
http://thisweekinbatteries.blogspot.com/2010/02/pull-plug-your-battery-will-thank-you.html

Yes, I heard those are great cells. I been trying to get in touch with A123 but they only want to deal with large dealers/ev manufacturers. Any leads where these can be obtained?

If anyone can recommend good pack distributors, or interested in a group buy (I can organize it and come up with initial investment), please let me know.
Thanks!

cell-man has A123 prismatic cells and he will assemble packs or sell the pieces for DIY pack assembly (see the threads below).

I am looking for 20 ah with maximum draws of 25 amps. What I am looking for is reliability and ease of cell replacement if necessary. No more nasty solder surgeries or cutting PCB tab connectors for me That rules out another Ping.

Any recommendations out there for good value and reliable Seller?


…Too rich for my blood.

I just received a quote from Michelle for the 48V 20ah Headway Pack and charger, $530 + $144 shipping. Hope she is legitimate.

The cell-man A123 prismatic cells are much higher quality than Headway. 16s 20ah of raw cells would be $800 plus shipping. You can buy the packs or the raw cells plus the parts for DIY solderless pack assembly.

Cell testing thread:
http://endless-sphere.com/forums/viewtopic.php?f=14&t=15093

"Testing the big 15 and 20Ah LiFePO4 cells is tough! *Pics*"

http://endless-sphere.com/forums/viewtopic.php?f=31&t=14832

"2.5USD per Ah for 15Ah and 20Ah 30C cells"

Solderless pack assembly:
http://www.endless-sphere.com/forums/viewtopic.php?f=14&t=15408

"Terminating the 15Ah and 20Ah Cell-Man cells"

 

[BLUESTREAK]

HI SNOWRANGER: MICHELLE who? I must have missed this vendor. That sounds like a very good price for a pack and charger shipped.

 

[snowranger]

I just received a quote from Michelle for the 48V 20ah Headway Pack and charger, $530 + $144 shipping. Hope she is legitimate.

That price looks pretty good I think if you compare it to what loose cells cost. $19x30 (or 32?) is around $600 then you need holders and busbars. I wonder if they are tabbed or threaded cells.

Thanks for reminding me. I just sent an email to verify.

HI SNOWRANGER: MICHELLE who? I must have missed this vendor. That sounds like a very good price for a pack and charger shipped.

Michelle Lu. She's on Alibaba.

The cell_man battery 20ah with charger sounds good, but it is going to run close to $1200 delivered.

 

[Green Machine]

Do you know the weight on that 20ah pack?

Be careful does sound a little to good to be true...

You should have them ship it UPS...you get it in like 3 days and its cheap...way better than ems.

 

[snowranger]

Not sure, but a little heavier than the Ping. Probably 25-26 lbs.

Shipping is by UPS and the cells are screw tab.

 

[swbluto]

I am pretty sure my Ping died from vibration and shock rather than heat. All bad cell groups were at the ends of the pack, and there were obvious signs of fluid leakage at the bottom of the pack.

Yeah, that's why I put foam liner at the bottom where the battery sits. (Or, if it's in a bag, I don't use anything because the bag material itself has "give" to reduce peak shocks and evenly distribute the forces.)