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WRX STI | 1 Mar 2010 01:11
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Re: New Thundersky specs

I think you will find that those ppl charging at 4.2v aren't doing it
because THEY think it is worthwhile, but rather because that was suggested
by TS in their manual.

Unless the chemistry has changed, I can only assume that the reason they
have changed the opperating voltage on their website has more to do with
what is available after charging, as to ensure they do not get into trouble
for false advertisement in countries that support such legislation.

The manual is pretty clear in what it recommends for charging, and even
though many have experimented with other parameters for charging and say
their results are more suitable, I tend to think that if the manufacturer's
manual says to do it in a specific way, then that is the way they should be
charged regardless.

Directly from the manual:
At 20C +/- 5C, the cell is discharged at a current of 1/3C3 till voltage of
the cell reach 3.0V, and then start to perform constant current charge at a
current of 1/3C3 under 20C +/- 5C till voltage of the cell reach 4.2V and
simultaneously switch to constant voltage charge. When charging current
value decreases to 5% of initial value, charging completes.

At -18C +/-5C, the cell is discharged at a current of 1/3C3 till voltage of
the cell reach 2.2V, and then start to perform constant current charge at
1/3C3 under -18C +/-5C till voltage of the cell reach 4.2V and
simultaneously switch to constant voltage charge and duration is 2 hours.
After that, Trickle charge will begin. Charging completes when charging
current value decreases to 5% of initial value.

Leslie
(Continue reading)

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WRX STI | 1 Mar 2010 01:23
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Re: run away [ accelerator pedal ]

I agree with the above for electrical disconnect - but this is still not
suitable for registration, as a non-electrical disconnect has to be used
(ie. full mechanical disconnect) - which only leaves two solutions I know
of:
1. A cable running to a circuit breaker switch that when pulled, activates
the circuit breaker; or
2. A cable or rod that when pulled or pushed, dislodges a fuse that is in
series with the traction packs positive of negative cable.

I'me sure there may be other fully mechanical options available, but these
are the two most basic options (read: that are not expensive to implement).
The only thing that would need to be found is a suitably sized circuit
brwaker and/or fuse to cope with the maximum current available from the
traction pack so as not to blow/break unintentionally.

On Mon, Mar 1, 2010 at 10:19 AM, Jeff Shanab <jshanab@...> wrote:

> >
> > I got it how about an ejector seat and a parachute!
> >
> > No seriously, the simplest solution is probably the best solution.
> > KISS principal... and don't use components that are undersized for the
> > application. Whether it be a contactor or a circuit breaker, whatever
> > your using as your final line of defense against a shorted controller,
> > it should be able to handle the job of disconnecting the battery pack
> > at maximum current.
> >
> > In the past people on this list have suggested that using multiple
> > breakers and/or contactors that add up to the maximum current, or
> > voltage is OK.  Don't do it folks.  Weakest link theory.  Each one
(Continue reading)

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Matrixel | 1 Mar 2010 01:36
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Re: Headway Battery Rust Issue

David,

A lot has to do with ones actual proximity to the ocean. I've lived at my 
present location just under a mile from the ocean now for over 17 years now. 
I'm one of those consumers that buy a car and hold on to them for a while, 
usually about 10 years.  I've never had a problem or heard of anyone else 
nearby with rust issues on their cars. A neighbor of mine grew up in a house 
on the beach and his cars showed signs of rust in just a few years. Where 
I'm located one unfortunately (or fortunately in this case) does not get to 
enjoy the refreshing smell of  sea air from my front porch. The salt just 
doesn't make it this far.

The only time I had rust issues were on my cars in NY and MA. The salt on 
the roads really does a number of the frame and lower body panels of the 
older cars.

The best strategy for dealing with rust on the beach is to lase your 
vehicle.

Charlie

----- Original Message ----- 
From: "EVDL Administrator" <evpost@...>
To: "Electric Vehicle Discussion List" <ev@...>
Sent: Saturday, February 27, 2010 11:16 PM
Subject: Re: [EVDL] Headway Battery Rust Issue

> On 22 Feb 2010 at 2:14, Travis Gintz wrote:
>
>> [Salt is] also a pretty corrosive compound that can eat away at the
(Continue reading)

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Tom Alvary | 1 Mar 2010 03:37
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Re: Headway Battery Rust Issue

Do not underestimate the reach of road salt in rust belt states.

About 20 years ago I was a Nature Conservancy volunteer keeping prairie 
remnants healthy in Northern Illinois. We were interested in the impact 
of road salt on the prairie plants, which were frequently close to the 
highway. IDOT, or somebody, came up with some money and had it studied.

It turned out that road salt was extremely mobile, because the traffic 
drove spray into the air an then blew salt dust all over once the 
pavement had dried. A two-lane highway could contaminate the ground with 
salt for over 1000 feet, and the Interstate could salinate the 
surrounding ground up to 3/4 of a mile from the roadway.

The same thing is also happening in your own driveway and garage in this 
region, whether you salt your property or not. Even in your home: just 
look at the salt stains on your shoes. Spreading salt on every paved 
surface all winter long is one of the most noxious things we do in this 
culture, and, I'm quite sure, a MUCH greater source of corrosion on 
everything than briny sea air, even if you keep a car off the road 
during snowstorms.

Tom
_____________________
Tom Alvary
Just A Tinkerer...
White Plains, NY
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EVDL Administrator | 1 Mar 2010 04:08

Re: related motor temp question.

On 28 Feb 2010 at 15:05, Ben Graves wrote:

> Can I burn up the motor without it getting physically hot? 

Absolutely.  

You might well be overheating the armature or brushes; they don't sink their 
heat to the motor case well, unlike the field coils.  

If you're getting an acrid, hot-phenolic odor, you may also be smelling 
overstressed brush pigtails.  Depending on the motor design and wire sizing, 
they can open like fuses in an overloaded motor.  At least they're readily 
replaceable, unlike field and armature coils.

David Roden - Akron, Ohio, USA
EVDL Administrator

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AMPhibian | 1 Mar 2010 04:59
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Re: New Thundersky specs


I believe at one point TS was also saying initial charge must be to 4.2 in
order to "activate" the cells.  However, this makes no sense since the cells
were tested for capacity at the factory, which means they would already have
been cycled fully at least once, and therefor "activated".  There has always
seemed to be some confusion, some of which may be translation problems some
may be that the factory doesn't exactly know what is best in the long run.

WRX STI wrote:
> 
> I think you will find that those ppl charging at 4.2v aren't doing it
> because THEY think it is worthwhile, but rather because that was suggested
> by TS in their manual.
> 
> Unless the chemistry has changed, I can only assume that the reason they
> have changed the opperating voltage on their website has more to do with
> what is available after charging, as to ensure they do not get into
> trouble
> for false advertisement in countries that support such legislation.
> 
> The manual is pretty clear in what it recommends for charging, and even
> though many have experimented with other parameters for charging and say
> their results are more suitable, I tend to think that if the
> manufacturer's
> manual says to do it in a specific way, then that is the way they should
> be
> charged regardless.
> 
> 
> Directly from the manual:
(Continue reading)

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Bill Dennis | 1 Mar 2010 05:07
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Re: New Thundersky specs

These specs seem to be for the new LiFeYPO4 cells, which contains 
yttrium.   So perhaps that account for the difference in the specs.

Bill
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AMPhibian | 1 Mar 2010 05:23
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Re: New Thundersky specs


Could be, but the Yttrium cells have been around for a while now and I think
the spec change was more recent.  Could be just a delay in updating the
info.

Bill Dennis wrote:
> 
> These specs seem to be for the new LiFeYPO4 cells, which contains 
> yttrium.   So perhaps that account for the difference in the specs.
> 
> Bill
> 
> _______________________________________________
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> 
> 
> 

--

-- 
View this message in context: http://n4.nabble.com/New-Thundersky-specs-tp1572914p1573143.html
Sent from the Electric Vehicle Discussion List mailing list archive at Nabble.com.
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damon henry | 1 Mar 2010 05:39
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Re: related motor temp question.


If you can smell it, I would definitely recommend adding forced air cooling.  I tried my 6.7 inch motor at
first without forced air cooling and did not like the smell, so I added the cooling.  This is a motor that Jim
Husted had a hand in birthing.  He took the time to inspect the motor after I had it on the road for a few months
with the cooling and was very happy with what he saw.  He then took me over to another EV (this was at a car show
where we had 20+ ev's on display) and showed me the difference in a motor that was not being properly cooled. 
Even though it was not one of his motors I could tell he was not happy that the poor motor was not being treated
properly :-)  As I recall the abused motor was actually substantially larger and would seem more
appropriate for the job, so perhaps the driver was not running it at high enough RPM's to allow the internal
fan to properly cool it.

You can see a picture of my cooling setup here http://home.comcast.net/~damonhenry/DSCN2545.JPG.

damon

> From: greenvw@...
> To: ev@...
> Date: Sun, 28 Feb 2010 15:05:50 -0500
> Subject: Re: [EVDL] related motor temp question.
> 
> I am also using a 6.7 in a heavier application. I get the occasional burnt
> electrical smell (motor has only a few miles on it) but immediately after a
> drive the motor is never too hot to hold my hand on it. Can I burn up the
> motor without it getting physically hot?
> 
> -----Original Message-----
> From: ev-bounces@...
[mailto:ev-bounces@...] On Behalf
> Of Jeff Major
> Sent: Sunday, February 28, 2010 2:42 PM
(Continue reading)

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Lee Hart | 1 Mar 2010 05:53
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Re: EV1 Motor Specs

Lee wrote -
>> The specs will be for the combined motor+controller. And these you can
>> find in any of the EV1 published data. I have much of it in print, but
>> you can probably find it easier on-line.

Rush wrote:
> Thanks for the suggestion Lee, but since he doesn't have the orig 
> controller, just the orig EV1 motor, in order to design a controller he 
> needs to know the specific operating parameters of the motor itself.

He asked for motor torque, power vs RPM, torque duty cycles, etc. These 
particular specs are a consequence of what the controller orders the 
motor to do.

For example, the controller applies a frequency, and the motor runs at 
the commanded RPM. The controller applies a current, and the motor 
produces the commanded torque. RPM x torque = mechanical power; so you 
need to know the voltage and current the controller outputs to know the 
power that the motor will produce.

The time that a motor can produce a given torque is directly set by its 
efficiency (how much heat it is producing) and its cooling system (which 
defines how fast heat can be removed). Again, you can't specify it for 
the motor by itself; it's controlled by external factors. The controller 
has a large effect on efficiency, and the cooling system control heat 
removal.

Now, if you run a motor on a *standard* supply voltage and frequency 
(say, 120vac 60hz) and the motor has a completely built-in cooling 
system (air cooled with an internal fan, for example), *then* you can
(Continue reading)

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Gmane