BatterySpace 37V/8AH Lipoly (pack cuts out at 20A sustained)

Reid Welch said:
the part number read aloud sounds vaguely filthy. :lol:
Click to expand...

So does your name... :lol:
 
I posted in the french forums of velectris, as I recalled they offer a 1 year warranty on their batteries, well apparently they do and are in talks to increase that to two years or 1000cycles. However, from what I understand of it the 8ah pack is designed to match their 16/20 amp controllers, Pascal said it would hold up well with a 30a controller, but that he wouldn't offer a warranty for that usage. Take it for what it's worth: The guy won't gamble that the battery will still have 80% capacity left in a year's time, if used this way. Instead, he suggested using a 17 or 13Ah pack for this. I have to conclude it's too much to ask of such a small pack.

Linky
 
Thanks for doing the inquiry! Pascal is great guy.

Bablefish translator makes for bad comedy,
Yet, "potato masher" comes through properly.

BTW, I'm trying ever so hard to get the idiots at Currietech USA to ship out the promised 36V brush motor controller.
It will have a lower current limit, probably 25A.

===

Yes, I would like to get a larger pack, but, alors!

I wonder how our English texts autotranslate to French? Even more oddly?
La Linky

Thanks Francois--good guy, have a footlong at Subway on me.
 
84.3Wh/lb is very good for a complete pack with what appears to be a BMS, but how many people will pay $2.77usd/Wh?

$154/Wh, but lower power density:
http://cgi.ebay.com/TREX-600-SIZE-Li-Po-Battery-4400mAh-18C-6S2P-MEGA-POWER_W0QQitemZ170094868786QQcmdZViewItem

Even paying full pop for A123 cells is around $2/Wh or so.
 
Here's the present state of my super stealth e-bike project.
This is why I yearn for cheaper lipos in large capacity cells which should Ideally be resistant
to mayonnaise.Mathurin please show this to Pascal for his thoughts.
"Potato masher", my eye!

The forks have yet to be fitted of course.

No-one will guess it's electric;
Everyone who sees it will think

gas.




yes, I'm into firm buns. front, side and rear collision protection. my swiss velo is the cheeze
 
Lowell said:
84.3Wh/lb is very good for a complete pack with what appears to be a BMS, but how many people will pay $2.77usd/Wh?

$154/Wh, but lower power density:
http://cgi.ebay.com/TREX-600-SIZE-Li-Po-Battery-4400mAh-18C-6S2P-MEGA-POWER_W0QQitemZ170094868786QQcmdZViewItem

Even paying full pop for A123 cells is around $2/Wh or so.
Click to expand...
If you want good cycle life and don't want to test other NEW battery manufactures problems, Kokams are here and ready to go! Sold IN THE USA.
 

Attachments

  • kokam.jpg
    kokam.jpg
    28.3 KB · Views: 3,315
Reid Welch said:
At present that is but a pipe dream.
"Planned manufacture".


:cry:
Click to expand...
Its NO pipe dream.EglePicher Baught Kokam a year and a half ago and this was planned then as manufacturing these batteries around the world.So far NOW Kokam eliminated FMA (there RC partner) and are selling directly from distributors and KOKAM USA.No competition when it comes to quality and cycle life.But pipe dream or not there Batteries are the best at the best price per cycle and they are readily available NOW!
 
Like I said before, even the best products can have issues. I have a brand new Kokam cell here that was down on capacity straight out of the box.

To be fair on the A123 comparison, a ready to run 8s pack for $2.55/Whr:
http://www.tanicpacks.com/catalog/product_info.php?cPath=101&products_id=757

When you factor in the longer lifespan of the A123 cells, they become an even better deal. It's too bad A123 is making us buy Dewalt drill packs to get the best price on the cells. Perhaps this is part of their plan, as I'm sure Dewalt isn't complaining about the high demand for their power tool batteries :lol:
 
EbikeMaui said:
Reid Welch said:
At present that is but a pipe dream.
"Planned manufacture".


:cry:
Click to expand...
Its NO pipe dream.EglePicher Baught Kokam a year and a half ago and this was planned then as manufacturing these batteries around the world.So far NOW Kokam eliminated FMA (there RC partner) and are selling directly from distributors and KOKAM USA.No competition when it comes to quality and cycle life.But pipe dream or not there Batteries are the best at the best price per cycle and they are readily available NOW!
Click to expand...


The status of US manufacturing for Kokam America seems to be an open question... while EaglePicher bought some Kokam in 2005, they went into bankruptcy in 2006. EaglePicher Industries, Ltd. (UK) may still hold a minority stake in Kokam.


http://www.kokamamerica.com/ka/docs/RC_FAQ_s_9.12.06.pdf

http://www.trumbullgroup.com/bankr-cst/egle/img/doc/eaglepicher_disclosure_statement_complete.pdf


:?
 
"let"? Let's say "pwned" :)

from the pdf link which Tyler magically materialized:
5. Q: How does Kokam America plan to improve its distribution and support of the RC market going
forward after the recent changes?
A: Kokam has recently established a direct support structure in the US as well as a company owned
distribution center outside Kansas City Missouri to support the RC market. In addition, as mentioned in
#4 above, Kokam is expanding its distribution channels by bringing on competent third party
distributors and dealers. Finally, Kokam is implementing plans to establish a production facility in the
US to support the North American market.
6. Q: How do I go about applying for a distribution or dealer license?
A: Please contact Larry Wright at the address located at the top of this letter.
7. Q: What other markets is Kokam selling into?
A: Kokam America has focused heavily on the Military and Aerospace industry over the past year, and
the same benefits the RC user enjoys has caught the attention of the US defense community and the
Aviation industry. Kokam was recently approved by the FAA and is now specified by Boeing on some
programs. In fact when Boeing releases its new 787 Dreamliner next year, Kokam is expected to be one
of the first Lithium batteries used in commercial aviation. Kokam is also involved in numerous other
high end applications such as medical equipment, power tools, electric vehicles, and robotics to name a
few.
8. Q: What is Eagle Picher’s involvement with Kokam, if any?
A: Eagle Picher has zero interest in the American entity and a minority investment interest in the
Korean entity. All sales in North America are through Kokam America.
Click to expand...
Thank you Tyler. You ought to be a distributor.
I'll write to Larry Wright with questions.
 
Reid Welch said:
... You ought to be a distributor.
I'll write to Larry Wright with questions.
Click to expand...

Well, first I'd gladly join you as a beta tester for the Kokam-fueled Cyclone driving a NuVinci CVP...


8)
 
Potato masher should be read as monster potato, it's kinda like saying that thing can dance.
 
http://forums.batteryspace.com/forums/viewtopic.php?t=8315&start=30
powerizer said:
Reid Welch said:
powerizer said:
Spark will damage PCM for sure.

Please don't add resistor on charging or discharging terminal !!! because it will reduce charging voltage..

May be the best reolutiojn is to use a safe plug to avoid any plug

Please return your pack and see what happen
Click to expand...
I'll return the pack on Monday.

I have done nothing for the pack except change the charging plug to a trailer type, because the supplied plug quickly welded itself.

My idea is misunderstood.
The proposal is a high value limiting resistor in the charger lead.
AND a SPST switch to =bypass= that resistor.

steps:

SPST switch OFF,
plug connector to battery pack,
SPST switch ON,
turn on charger.


The pack would always have =normal charging current and voltage=
there would never be any spark. A 1 to 10k resistor may be appropriate.

I would never charge with added resistance in the circuit.

Is this clear now?

=I leave it to you= to design some way to stop the sparking so the PCM will not be damaged.


Thanks
Reid
Click to expand...


If plug get melted, means got wrong polarity somehow, PCM will get damage.
We will add a polyswitch on the charging terminal, and use a coaxis plug.
Please pay attention on polarity on both charging and discharging terminal ---- The best way to protect battery is make correct polarity.
We thought to add abreaker to discharging terminal , but it is too big and too expensive.

Please don't change our connector on charging terminal--- you shall change the connector on your side.
Click to expand...
 
Edit message
From: Reid Welch
To: powerizer
Posted: Tue Apr 03, 2007 4:59 am
Subject: Return of pack for refund







Hello John,

The pack has been discharged to 36V and safely packed for return.

I've decided that this item is not reliable enough for my needs.

I have done everything so carefully. The charge connector is quite waterproof; and no water has gotten on anything.

The spark that occurs on plug-in has been present from the first time I charged the pack.

I have said, and will repeat, that the spark seems to be caused by an inrush of current to the charger's filter capacitor. That's just my guess.

The pack works, but it cuts out. We know these new things (new PCM design) require de-bugging.

I've been patient and so have you been patient.

For now I just want to have a refund and look around for other battery options.

I do regret cutting off the charger's original two-pin plug.
The charger only puts out 41.8V at most. The supplied barrel plug adapter was very poor--the spark destroyed it within two charge cycles.

I saw the two-pin charger plug as yet another -risk- of accidental shorting--it can make contact with reversed polarity; so I cut it out of the cord and put in a good trailer connector.

Ah well, I have tried so hard to -promote- BatterySpace's best interests.

My e-bike friends on the Endless-Sphere forum think I should not be risking and making myself the beta-tester for the new pack.

I did not know when I purchased the pack that it was so new and unproven.

What a difficult business. I would like to continue as a BatterySpace customer and promoter.

Your firm has fine people and products. It's just regrettable the lithium polymer pack is not quite ready yet for even experimental users like myself.

IF my cutting of the charger cord is to be blamed on me, then I will pay for the charger. But really, I feel like I've done so much to try to make this right.

Thanks for understanding my position.

When you get the pack back and see what is wrong, I hope the fix is easy.
But I do not want this pack again---I will buy some other pack which will be better tested and warranted for a longer period of time.

So, when you get the pack back, please refund my credit card.
Thank you,

Reid
Click to expand...
 
TylerDurden said:
Reid Welch said:
... You ought to be a distributor.
I'll write to Larry Wright with questions.
Click to expand...

Well, first I'd gladly join you as a beta tester for the Kokam-fueled Cyclone driving a NuVinci CVP...


8)
Click to expand...
Ha ha, but I'm fresh out of humor today. And I'm never gonna be a beta tester on my own nickels again.

huh.

---No Kokam for me either, not at this time. Pie sky why.

I am willing to give our Chinese member-liason my order---I think he's for real; he makes packs every day.

If he takes a CC then we're both protected.

http://endless-sphere.com/forums/viewtopic.php?t=238&start=30
 
If he takes a CC then we're both protected.
Click to expand...

For even more protection, can I have your credit card number too? (They're worth a pretty penny on the black market, you know...)
 
Well...

You might re-consider the drill-pack concept:

Available Nationwide
90day return at any HD/Lowes
Scaleable (try 2 MilW for 56V 3Ah, if you like it, get two more, etc.)
5 Yr warr.
Easily liquidated on ebay if you upgrade later
Useful around the home if you get tools too

Homebrew plans are in process for selectable input/output voltage

Sadly the Ridgid bargains are now scarce, but the lifetime agreement is an interesting tidbit (same cells 6@24V).


:?:
 
Reid, we have the poll function, so within a price range, you could leave it to democracy to decide your next battery. :D

One vote (3) Milwaukee V28 packs in parallel.
 
If I had the dough, I would buy the 13ah nimh tabbed loose cells and fill the currie battery box with as many as it would hold and then if they don't all fit, attach the rest on the side or in water bottle.

But the best bargain is the 10ah nimh tabbed cell at only $7.16 a cell at BS.
 
BS Li-Poly:

$370/10 = $37 per cell.
$37/8 = $4.6/ Ah


Milwaukee drill Emoli:

$380: Drill, Charger, 2 28V batteries -$75 HD coupon
Sell the drill on ebay -$100
2 batteries & charger for $205
Charger Value: $55
2 Batteries for $150 = $75 per battery

$75/7 = 10.71 per cell
$10.71/3 = $3.57 per Ah


Edit:
Price includes 5yr pro-rated warranty (see attached), 2hr recharge & no fire/explosion.

8)
 
You must log in or register to reply here.
Back
Top