Confirm, please, that this LiPo pack is a goner?

[Reid Welch]

The unit was purchased over two years ago.
I got ill soon after the purchase, and set aside the project bike; left the 36V/15Ah LiPo pack at near full charge,
knowing it would sink in voltage, very slowly....but..... I did leave the BMS connected.

I suspect that is why the battery is stone cold dead today: the BMS must draw some small current?
Is that how they work? It must be just that. So, the neglected battery went totally flat-line. LiPo. Cobalt.
Nasty if messed with like I'm about to try.


Picture shows the (green) connector to the lid's BMS, that is now disconnected, but was connected
for the idle years, until yesterday.

Probes to the red and black output of the pack itself show: zero voltage.

Confirm, please, that this is indeed, safe only to throw away?

If that is the case: forget it (I am in a state of denial of the truth, ahem), do you have
any favorite ideas for a replacement?
I have yet to start buying/shopping for a front hub for this new bike,
but will, apparently, also need to buy a new battery.

Toss the battery? Unsafe now to recharge? I know the answer.... dang it.

 

[vanilla ice]

Get some bare cells with the same chemistry and reuse the case and bms.

 

[marvingalaxy]

You might be able to save it but you will have to leave it in the refrigerator for several days. It's actually not that hard. Here is what you do:

Put the battery on the middle shelf. You probably need to put the glass of salt water in first as that goes behind the battery. It doesn't matter what order you do the rest as the process is fairly slow. I'll just explain the arrangement and you can choose the steps in order of your convenience. With the glass of salt water behind the battery on the middle shelf, put three more glasses of water surrounding the pack. Salt is in the back, distilled on the right, tapwater on the left, and brackish water goes up front. The levels of the water should be even with at least 8 ounces (about .25 liter or more) in each uncovered glass. The next part determines how much amp-hours you want to recover. Put sliced smoked turkey wrapped in foil on the shelf above the battery. Ham goes underneath the pack but it must be wrapped in plastic. You must use aluminum foil and heavy plastic like a freezer bag and not thin cling wrap. The conductive aluminum and insulating plastic provide the capacitance necessary for the process to work. The bad part is that the ham will end up tasting like turkey and I really prefer ham.

You aren't still lamenting your dead battery after all that, are you?

Seriously, the good news is that battery technology has improved and you can get a LiFePO4 pack that should never explode and probably will last more cycles than LIPO. My uneducated guess is that you may have encountered the problem of a full pack getting dendrites or maybe the cell voltage crept too low and destroyed them. Two years is already about half the life of LIPO so you weren't going to get thousands of gleeful charges from this pack anyway. If your monetary and weight budget can handle it, more experienced people around here recommend at least 20AH packs so the discharge rate stays lower to maintain pack life. I'm a noob but I think I will take their advice and either have a 28AH Ping pack made or I will parallel two 16AH Ping packs.

What is the discharge limit on that BMS? I'm not smart enough to solder together my own pack but you might have the ability to make your own if you get new cells. What motors are you thinking of getting and what is your intended use (range, speed, terrain)?

 

[swbluto]

From reading the posts on rcgroups.com, it seems letting lipo's lie makes them die kind of like lead in the same way it becomes dead.

 

[dogman dan]

Bummer man If you have, or are getting a 500-750 watt bike, the sise you want if you buy a Ping lifepo4 is 20 ah. roughly, you want 1 amp hour per average amp draw on the pack for the best longevity. You can stretch this and run a 1000 watt motor on a 20 ah, but the 5304 cyrstalite is pushing it, more like 2000 watts usually. For the least expensive lifepo4, go to Pingbattery website. He is totally to be trusted. Others are a pays your money and takes your chances. A few of the other ebay vendors have sent real junk.

The other new cells out there, PSI, Lifebatt, and various toolpack cells, can discharge a lot more, and only need enough ah to cover the range you want. These tend to cost roughly twice the money per ah than Ping.

 

[knoxie]

Hello Reid

Nice to hear from you! been ages since you posted on here, hope you are over your illness? shame about the battery, I have the exact same battery its also about 2 years old but has been used fairly regularly and it still works fine the problem is the BMS it will draw current from the battery when it is not being used, are you sure that there is no voltage from the pack? I would be very surprised if it was totally dead?

If you are going to toss it you have nothing to loose in trying to re-charge it, I would recommend doing this outside away from your house just in case :? if you loose the charger as well then thats a shame but not the end of the world as you most likely cant use it for anything else.

I have seen them sit 2 years or more and still charge ok though so it is worth a go.

Hope your on the road to recovery now, keep us all posted.

Knoxie

 

[Reid Welch]

Hi guys, thanks for the confirmation, and for for the humour, too!

Dear Knoxie: the battery, at the output, is stone dead.
I have tried only the OEM supplied charger.
When I put that charger to the direct red and black output connector:
the little charger's green light goes off, and nothing but "ticks" from the OEM charger;
its internal fan even stops running.

I will try the auto battery charger next, out of doors, on a variac, and see if the cell pack accepts current.
But we know: any LiPo that's gone dead is a permanent, future hazard, for fire and explosion.

It would be best just throw the thing away, and keep the BMS for sending to you, Knoxie,
in case it might be of some future use to you from your bin-box.

OK, now to try the auto battery charger, just current, watching the amperage, and see if anything comes up.
WELL OUT OF DOORS.


-----you asked? I confess:
how am I? Great!
I'm not a kid anymore; not at 54.
But I passed a recent physical with perfect results.
I will not die of high blood pressure (SLE side effect) or kidney failure (SLE end result for males)
So here I am, eight weeks in remission from SLE.
I think I will live in full remission indefinitely now.
"valium lupus" (google terms), for the "cure" that I discovered, no thanks to any MDs.
---
Self portrait, ten second timer, of fifteen minutes ago, in front of the two day old cruiser bike
I forgot to smile.

Have already refitted the Bontrager tires from the aborted Currie Mongoose Cruiser.
Have found (lucky me) that old suspension seat. (Knoxie told me about it way back when) It fits perfectly;
gives several inches, too, of set-back, for a more crank-forward pedaling style.
The bike rides supremely well.

I will be going for a 16 to 20 mph, throttle controlled, casual
STEATH cruiser-look. No battery kit bags nor front or rear caliper brakes;
just a minimalist, throttle-fed bike for helping along, and for fun and all that.
I don't want to go so fast anymore, not with a coaster brake, only,
and not on this 24/7 need for Valium (!) to stop that "body wants to kill itself", which is what "SLE is about.
Valium tends to make a person clumsy at first. I'm not so clumsy lately (tolerance for the drug).
It does not make me "high" or "drunk" or any of that, but for some people, it is a pleasure drug.
Enough of that. I am "cured" for now, thanks to a simple, cheap, generic prescription drug.
----
I am so happy to be back here.
Will need a lot of hand-holding to get this minimalist bike electrified,
K.I.S.S.

A small front wheel hub motor (and the Nano is still not fully ruled out) is the first thing to get for the bike.

Thanks to all, again,

R.

(edited for typos)

 

[Reid Welch]

..I will try the auto battery charger next, out of doors, on a variac, and see if the cell pack accepts current...

One hour later: the pack shows 19V.

Here is the set up:
http://www.youtube.com/watch?v=8uFN73V4zXk&fmt=18
Will continue the slow input of current, and if it "holds",
raise pack voltage to a point where the BMS can be re-connected,
and then try to see if the stock charger will operate as it once did.

--
All done well out of doors in case of you-know-what.

That aluminum container is welded, sealed, not vented,
potted contents. It will explode if ever a cell should pop.
Massive, unstoppable fire will result if that happens.

more later. give it time to de-dendrite, so to say. expect nothing.

 

[vanilla ice]

Hope for a recovery, expect nothing.. sounds like a good plan. Doesn't hurt to try. Is that a thudbuster on there?

 

[knoxie]

Hi Reid

Yes great to see you back online, most of the old crowd are still here with plenty of new ones to boot! there is a load of info and helpful posters on here to answer pretty much any question that you may have. Go steady with the battery we dont want any fireworks! its worth a try, shame that you never charged it up, I had 2 that were sat about for a while but they are fine still.

Bike looks nice, and yes a Nano or a cheap golden motor in there would do you, there are quite a few hub motor options, the BMC is a nice candidate as well if you want nice high torque and light motor.

Have a good weekend!

Knoxie

 

[Reid Welch]

Hi Vanilla and Knoxie;

a two-in-one reply:

YES, that is a Thud Buster. It was wrapped in that sort of self-adhering Ace bandage material,
back when I had that seat on the blue Currie Mongoose cruiser. The wrap does two things:
makes the mechanism stay clean, and makes the seat and its post "uninteresting" to thieves.
Have some rolls of the same thin, self-sticky stuff, in black (must find them) and will re-wrap the Thud Buster in black,
later.

---
Knoxie: Two hours now into the "charging". Turn the charger off: reads 21V on the multimeter.
If this is to work at all; if any "de-dendriting" is even possible, I must give it lots and lots of time
at low voltage, to "re-form" (if possible), perhaps for days? I don't know, of course, I don't know....
But I will at some point raise the voltage to a much higher level, like 29V, and then reconnect the BMS,
and plug in the small, OEM charger (which outputs about 42V open circuit), and learn then whether the BMS
will allow the pack to come to "full charge" as per normal. And then, by light bulb-load test, see if any actual
useful capacity remains in the thing.

Knoxie, gimme a link to the current style/s of BMC motor?
I want light weight, light duty, small-sized, stealth. [/b]Geared is best for me, of course, cos it freewheels freely.

In thinking about the troublesome little Nano motors: too small for heavy duty use (the heat, the heat).
Their "gearing" is planetary, but by hard steel balls against hard steel races. I can see that hard use will kill them in time.
But I won't be giving the tiny thing hard use. Have no hills here and will mostly just go 'fast' for short periods of time,
and pedal assist. Its appeal points: totally free wheeling, so I can pedal manually without the least drag,
and it is "stealth" supreme, and won't adversely affect the "feel" of the bike in normal running.

So, a link to the latest and smallest sort of BMC would also be appreciated.
Its gearing is planetary, and makes gear noise, unavoidable.

The theoretical advantage of the Nano type: less frictional losses from its planetary steel balls:
no pinion teeth meshing, no pinion posts, no "gear" noise per se, just a rolling sort of sound.
If I don't abuse the Nano, it might work...but this is all just dreaming: no Nano is sold here in the US of A,
not for a fair price, anyway.

thanks for the helps, as always, you guys are great!

Reid

 

[Ypedal]

Hmmm.. interesting test for that battery !!! might be busting some myths !!

Not everyday we can convince someone to let a Li Cobalt ( that thing is a Point1 right ? ) drain to 0v and then charge it !!! but this is a perfect opertunity .

Make sure it's far from the house, and have a hose or bag of sand handy for an emergency.. :lol:

On topic of geared motors.. check out http://www.ebikes.ca for ezee kits !!! light weight, geared, freewheeling, good power.

 

[knoxie]

Hi Reid


The superkids were doing the BMC and http://www.texaselectricbikes.com/catalog/geared-motr-p-219.html er doing them also, there is a poster on here that is doing them as well the uprated 600W version, link to the video of it here.

http://www.youtube.com/watch?v=kiX8HNmx6Mg

If you search about you may find others as well.

Good luck with the battery!!

Paul

 

[fechter]

Most Li-Co chemistry BMS circuits have a feature to severly limit the charging current if the cell voltage is below the LVC value. It may take a really long time to get the cells up enough for the charger to kick into the normal charge current (days).

The Bafang motor is similar to a BMC in construction, but smaller in size (and price). They have gears, but are extremely quiet. At high power levels, there have been issues with the nylon gears stripping, but they work fine if you limit the current enough.

 

[Reid Welch]

Multiple replies in one post, to your helps above:

Ypedal: thanks for the link to Justin's offerings.
The cost isn't cheap, but the service and reputation of his firm (and yours) are impeccable.
I may end up going for that ezee front hub/wheel kit. I got the DrainBrain from him years ago.
It was boss.
The ezee specs are just about ideal for what I want: light to medium duty, a 20 amp drain, max,
and I can choose a thumb throttle. His documentation is great. The planetary gears of tough plastic
give some quieting, at the possible expense of ruggedness: a good trade off. Anyone else here ever
run a Model T Ford? Planetary low gear: noisy as all get out, usually: all metal, spur gears = lots of harmless whine.

Report on the progress of The Dead Lipo Battery? The aluminum mystery box has had direct charging today
and periods of rest, and retains a voltage reading of about 21V now, after long rests.

I probably need to get the voltage up quite a bit higher before the BMS, when reconnected, will allow
a regular charge. ALL OUTDOORS. "Run for your lives, she's gonna BLOW!!!!" (just might do exactly that)
So, I should consider next, the future battery options.

Knoxie, thanks! I just viewed and rated that cited video, http://www.texaselectricbikes.com/catalog/geared-motr-p-219.html
and left a comment there. More bike and motor than I need or want, but it sure is impressive, what they are doing there.
So "ampdavolts" (me) has subscribed to their videos to come.

Most Li-Co chemistry BMS circuits have a feature to severely limit the charging current if the cell voltage is below the LVC value. It may take a really long time to get the cells up enough for the charger to kick into the normal charge current (days).

Yup. And even then, if then, I can't imagine it being safe. Why, even if one cell were to short
and puff: it's all in a welded al. container. It will literally explode, and self-fuel as a grand fire. I should not use this battery
even if it "comes back", at all.

The Bafang motor is similar to a BMC in construction, but smaller in size (and price). They have gears, but are extremely quiet. At high power levels, there have been issues with the nylon gears stripping, but they work fine if you limit the current enough.

Do they have a domestic seller? Is the motor available in-wheel, ready to mount? If not, this is why Justin's "total care" ezee system appeals right now. Seven bills for the kit, sans battery, delivered. Seven bills.... (I need to eBay some junk and raise funds!). But he's such a great dealer.
You get what you pay for, or sometimes, less; but not from Justin's firm, nor Ypedal's emporium of great powers.

Hmmm.. interesting test for that battery !!! might be busting some myths !! (SNIP)

This is what I love about you: your wry sense of humour matches mine. Yeah, that's the ticket...I'm gonna bust some
"myths", and the fire department will be at a loss to put out the conflagration and the papers will report The Fire that Could Not Be Extinguished.


Oh, happy days, these happy November summer days.... (I live in sunny, Florida, ya' unlucky gimps!)

 

[fechter]

For the Bafang motor, check here: http://endless-sphere.com/forums/viewtopic.php?f=9&t=6388

It may not be as nice as the Ezee, but somewhat less expensive. Last time I checked a while ago I think Justin was sold out of the Ezee motors. Hope he got more.

 

[Reid Welch]

Thanks for that info abov, fechter!
I will check with Justin soon. Am emotionally prepared now to spend the money
to get the "better" motor from that known-great guy, even if it means a wait for stock.

BTW, hey, lookie: this Time Bomb battery, topic of this thread:
it has held its 21V for hours now, and can even make a 130V/200W filament glow!

Ha ha, this is going to be some coming event: the battery CAN be charged further...
...and El Predicto Reid, here thinks:
we are going to get a new version of the BIG BANG theory in practice

 

[Reid Welch]

From page one:

Bummer man If you have, or are getting a 500-750 watt bike, the sise you want if you buy a Ping lifepo4 is 20 ah. roughly, you want 1 amp hour per average amp draw on the pack for the best longevity. You can stretch this and run a 1000 watt motor on a 20 ah, but the 5304 cyrstalite is pushing it, more like 2000 watts usually. For the least expensive lifepo4, go to Pingbattery website. He is totally to be trusted. Others are a pays your money and takes your chances. A few of the other ebay vendors have sent real junk.

The other new cells out there, PSI, Lifebatt, and various toolpack cells, can discharge a lot more, and only need enough ah to cover the range you want. These tend to cost roughly twice the money per ah than Ping.

Well, here's their site.
It looks like good value indeed
http://www.pingbattery.com/servlet/the-36V-LiFePO4-Battery-Packs/Categories
I need to read up more about Ping Batteries---that data will be found if I search the threads here.
I think about: cells keeping in balance, BMS reliability, etc.
But, yeah, ever so much safer than Lithium cobalt poly pouches!
And everyone here who has bought a Ping is pleased so far?
Thanks for the tips, dogman! cheers!

Reid (gonna hock his granny's gold capped teeth for cash....tough job, that....'cause she is a light sleeper )

 

[Ypedal]

How much range do you need on a charge ?

The Pings are among the better of the " Covered in Duct Tape " packs, but imo require some care and attention in the mounting area.. ( LiFePo4 chem, but in " soft " foil pouches.. )

Your Point1 was Li Cobalt..

The eZee comes with Li Manganese, ligher than LiFe per ah, higher V per cell, 500 or so cycles rated.. but for a 10ah pack it's nice and light.. well boxed up, with good quality charger.

 

[swbluto]

It's an interesting to see that you're back, Reid. The only thing I associate you with is this Site's founding from the "ancient threads" and Xyster, so I assume LiFePO4's prevalence is kind of novel to you?

(Back in the days, it seems like it was called "LiPO4" for some reason. Maybe that's Li-poly? Hahaha...)

Anyways, it appears you were gone starting May 17, 2007. So it's been a long e-time...

 

[dogman dan]

I wouldn't say everybody that bought a ping is happy, but I sure am! With these particular batteries buying one too small for the motor is the most common problem, followed by not boxing them up and then dropping the bike. They really do need more than a bag to protect em. A very few folks have had a problem that Ping has really worked hard at solving. When you consider shipping, I am amazed that anything arrives in working condition! But if you stick to the standard formula, 20 ah pack for a bike up to 1000 watts, there have been very very few complaints about a ping pack. Plenty of problems with certain other sellers and their 18650 round cell packs though. There are better lifepo4 cells out there for sure, but the moderate power ebikes don't need them. In your case though, if your rides are short now, a 20-30 mile range ping pack may be more than you need and smaller, lighter A123 cells or something may be a better thing for you. But at this time, you have to use tool packs and do some fabricating to use the better cells and make a small power supply.

Btw there has been a 180 watt gearmotor for sale on ebay lately pretty cheap. Might be just right for a cruiser if slow is what you want.

 

[docnjoj]

Welcome back, Reid! When U look on Ebay, sign up for Live Search from Micirosoft! I just save 30 % on my new Ping 48V 20 ah! Similar savings on lots of stuff. Maybe bring back that MY1018 and collaborate with Tyler again!
Warm personal regards
otherDoc

 

[powermed]

Is there any voltage from the pack? I didn't see it in the thread - I fixed my brother's LiFePO4 pack which had a similar problem by giving it a partial charge directly from a low current 36v source. Sometimes (I think it was mentioned) chargers have a low voltage limit for safety. If they can be brought up slowly to some point, the original chargers should be tried again. If the pack measures zero or negative I'm guessing their toast.