EV Digest 2611
Topics covered in this issue include:
1) dc/dc convertor choices?
by Jim Coate <[EMAIL PROTECTED]>
2) Re: dc/dc convertor choices?
by "Roy LeMeur" <[EMAIL PROTECTED]>
3) Re: BMS cost (was Re: LIN bus link)
by Lee Hart <[EMAIL PROTECTED]>
4) Re: You Don't Have to Plug It In!
by Lee Hart <[EMAIL PROTECTED]>
5) Re: Inspired Corporation's Product - Part 2 (long, but please read!)
by "1sclunn" <[EMAIL PROTECTED]>
6) Re: [RAV4-EV] question about turning a RAV4 EV into a
grid-chargeable hybrid
by Peter VanDerWal <[EMAIL PROTECTED]>
7) Re: EV1s waiting,rant, an' stuff; more! Bux Dept
by "Bob Rice" <[EMAIL PROTECTED]>
8) Re: pick-up truck dimensions?
by Peter VanDerWal <[EMAIL PROTECTED]>
9) Re: dc/dc convertor choices?
by "1sclunn" <[EMAIL PROTECTED]>
10) Battery Choices
by "EV'r up LATE" <[EMAIL PROTECTED]>
11) Re: Inspired Corporation's Product - Part 2 (long, but please read!)
by Lock Hughes <[EMAIL PROTECTED]>
12) Re: dc/dc convertor choices?
by "Tony McCormick" <[EMAIL PROTECTED]>
13) Re: Inspired Corporation's Product - Part 2 (long, but please read!)
by Sam Harper <[EMAIL PROTECTED]>
14) Re: pick-up truck dimensions?
by Peter VanDerWal <[EMAIL PROTECTED]>
15) Re: Inspired Corporation's Product - Part 2 (long, but please read!)
by Peter VanDerWal <[EMAIL PROTECTED]>
16) Re: EV speed record
by Henry Deaton <[EMAIL PROTECTED]>
17) Re: Inspired Corporation's Product - Part 2 (long, but please read!)
by "David Roden (Akron OH USA)" <[EMAIL PROTECTED]>
18) Re: BMS cost (was Re: LIN bus link)
by "1sclunn" <[EMAIL PROTECTED]>
19) EVI ICS 200-B charging unit
by beckettw <[EMAIL PROTECTED]>
20) remove
by [EMAIL PROTECTED]
21) Lithium fire control WAS:Re: Inspired Corporation's Product - Part 2
by Lock Hughes <[EMAIL PROTECTED]>
--- Begin Message ---
I had a depressing thought today... with Damon/DCP is putting on-road EV
stuff on hold for a while, what choices are left for high(er) voltage
dc/dc convertors? There is a rather large gap between 120v Curtis units
(if those are even still made) and 336 volts which is the ticket into AC
systems with the built-in dc/dc.
_________
Jim Coate
1992 Chevy S-10
1970s Elec-Trak E20
http://www.eeevee.com
--- End Message ---
--- Begin Message ---
Sevcon makes a wide variety of DC-DC converters.
Contact Roderick at evparts.com, he should be able to hook you up with one
for your requirements.
Damon may still have a few available.
-Jim Coate wrote:
I had a depressing thought today... with Damon/DCP is putting on-road EV
stuff on hold for a while, what choices are left for high(er) voltage
dc/dc convertors? There is a rather large gap between 120v Curtis units
(if those are even still made) and 336 volts which is the ticket into AC
systems with the built-in dc/dc.
Roy LeMeur Seattle WA
My Electric Vehicle Pages:
http://www.angelfire.com/ca4/renewables/evpage.html
Informational Electric Vehicle Links:
http://www.angelfire.com/ca4/renewables/evlinks.html
_________________________________________________________________
Protect your PC - get McAfee.com VirusScan Online
http://clinic.mcafee.com/clinic/ibuy/campaign.asp?cid=3963
--- End Message ---
--- Begin Message ---
Lee Hart wrote:
>> You need to price out a "cheap" light fiber. Fiber optic systems
>> are generally far more expensive than wire and connectors.
Otmar wrote:
> No need to speculate, here are the details from Digikey.
> Phototransistor, FB121-ND $3.65 ea $2.37/100 IF-D92
> Emitter: FB118-ND $3.48 ea $2.25/100 IF-E91A
> I believe the fiber costs about $0.40/ foot in 100 ft rolls.
>
> They are certainly much more expensive than wire and connectors.
> I believe this is too expensive to put on one module for every
> battery, though it would be possible.
>
> I have a personal goal in this design having to do with safety.
> My goal in designing this EvBus is to minimize overlap of the two
> systems. I would like to eliminate all high voltage wiring that is
> not required for carrying power...
Here's the problem. We have lots of "things" in the high voltage section
that we want to monitor. Here are just a few:
- individual battery voltages
- individual battery temperatures
- individual battery water levels (if floodeds)
- total pack voltage
- total pack current
- controller voltage
- controller current
- controller temperature
- motor temperature
- motor currents (each winding)
- motor voltages (each winding)
- motor speed an/or position
There are of course many ways to approach this problem.
1. You can have a central control box, referenced to ground, with
separate high voltage isolation for every signal. Now all your
dash indicators and operator controls are low-voltage and ground
referenced.
2. You can reference the whole control box to pack voltage. Now you
don't need isolation on any HV signal, but you must isolate every
signal coming out of it to the dashboard and operator controls.
3. You can have a mixed-mode system, with some parts ground referenced
and some parts HV-referenced. This can make it hard for various
parts of the system to communicate; for example the E-meter is
HV-referenced, so it is hard to use data from it for other systems
without adding isolation.
4. You can split the control system in two; half is HV-referenced,
and half is ground-referenced. Isolated cables connect the
two. There is a "data concentrator" box on the pack side, which
monitors all the HV signals and concentrates their data into a
single data stream. It communicates with a "control box" which
is ground referenced, and runs the dashboard and monitors various
driver inputs. It communicates with the "data concentrator" via
another isolated data path.
I think Otmar is describing system type #4. It is a conservative design,
common in large, expensive systems. But it tends to be fairly complex
and expensive. It is great for prototyping, research and development,
and high-end production systems. But due to cost, this approach is
rarely seen in consumer products.
Most EVs have *no* battery management at all. Their designers weren't
willing to spend *anything* to monitor or control individual module
voltages. When you do see battery management systems, it is either being
done as a research tool (someone desperately wants the data), or they
are forced to add one (such as exotic batteries that will fail
spectacularly without one).
This tell me that the best-selling battery management system is the
*cheapest* one. So, I'd look for the absolute minimum functionality
needed, and the absolute minimum amount of hardware needed to implement
it.
The simpler the hook-up, the better. Ideally, it should have only two
wires; to the + and - of the battery. As soon as you have even one wire
(or cable, or hose, or fiber optic) per battery, complexity and routing
problems quickly grow.
Since HV packs need to be well insulated to prevent shock hazards, they
will almost certainly be fully enclosed. That means they will very
likely be dark inside. Thus, light seems a perfect medium for carrying
data. The transmitters (LEDs) and receivers (phototransistors) are very
cheap. We should be able to have a single receiver somewhere inside each
battery box to receive data from all its battery modules, with no fiber
optics at all -- just air.
A trivial circuit can send battery voltage as frequency modulation on a
pulse of light. The repetition rate can be the battery's serial number.
If the rates are all different, they won't synchronize; if two happen to
transmit at the same time, they won't at their next transmit time.
These modules could function like Rudman regulators, and include a load
resistor to clamp the battery voltage if it gets above X volts. This
way, no data channel is needed going *to* the modules. This circuit need
be nothing more than a light bulb and zener diode.
So, what I'm thinking of is a circuit with a BOM (Bill of Materials) of
less than $1. It has to be cheap, or not enough people would buy it to
justify building it. (Witness; there have been dozens of battery
management systems that cost tens of dollars per battery; they all have
a negligible market penetration).
--
Lee A. Hart Ring the bells that still can ring
814 8th Ave. N. Forget your perfect offering
Sartell, MN 56377 USA There is a crack in everything
leeahart_at_earthlink.net That's how the light gets in - Leonard Cohen
--- End Message ---
--- Begin Message ---
Lawrence Rhodes wrote:
> Seems to me you could put in a relay to reset just the system and not
> things like the radio and other saved data whatever that might be.
Unfortunately, Toyota has merged and twisted together all the computers.
They all talk to each other, and check up on each other. It's been
proving hard to outsmart them. There is a group of people working to
crack the network codes between the various systems, but they haven't
done so yet.
> Seems like the Prius as a pure electric would go a good 25 miles if
> you took out the engine and gastank and put batteries there.
It would do a lot better than that! It can go 5-10 miles on its present
6.5ah pack, except that the electronics fights to keep you from going
any deeper than 50% SOC or any higher than 75% SOC.
--
Lee A. Hart Ring the bells that still can ring
814 8th Ave. N. Forget your perfect offering
Sartell, MN 56377 USA There is a crack in everything
leeahart_at_earthlink.net That's how the light gets in - Leonard Cohen
--- End Message ---
--- Begin Message ---
Hi Sam
I like your math , I do that same kind of math when I want to convince my
wife that the "fish I catch will off set the price of the boat"
It sounds like you are building a car for yourself and want to try some of
the new stuff that's out there .
Or should I say all of the new stuff. Why not move more towards he middle
of the road for starters. It will cost less and will have a better chance of
working well. Hi performance cost money . If you look in the album your see
lots of conversions with golf cart bats . They won't give the neck snapping
performance of YT's but the price is a lot cheaper .of course YT's are a lot
cheeper than what your talking about also. You are talking about a 7k pack
of something untested were 1 or 2k gives known results .
>
> Obviously the electric is cheaper to me, or equal to everyone else.
> But what would I have in my electric to make a two-seater worth that
> much? Well this is what I think a Distortion Networks conversion would
> have to have:
Saving money is a small part of driving an EV
> -The AC drive system I've spoken about, 100kw, with regen, and reverse,
> and diagnostics, and all those nice things
> -A completely replaced interior (new plastics, new seats, Wet Okole
> neoprene seat covers for that cool feeling, a nice stereo (I'm thinking
so your not talking about a from the ground up new car to start with but
converting an old one?
> Eclipse and JL Audio)
> -New paint job
ok
> -Lithium-Ion pack, say around 22kw capacity
??? not my choice. I'm waiting to see how others do with them.
> -A nice fat PFC charger - think you can make me one for Lithiums?
> Maybe i'll have to settle for less
less problems
> -All the comforts of an ICE
What ever Ice you convert the comforts will come along.
> -My trunk (wow, the quarter-ton lithium pack could afford me such a
> thing)
you can still have a trunk with lead bats
> -An automatic or CVT transmission (I like the CVT better, cuz we can
> program it to stay within certain RPM ranges to be most efficient)
more R and D $$$$$$
> I'm sure I could come up with more
more money?
> I could probably get enough funding to build ten of these units (around
> the above price, maybe, just maybe). My question to you: Do you think
> there are enough people to buy ten of these units?
One problem with people buying an EV is that they want to know that there
will be somebody to fix it if it brakes .Will you do that? With all the hi
tec stuff you are talking about using this is going to be important.
Before you start planning 10 to sell lets plan yours . If your in Ga than
your not to far from Florida . Why not come down and try one of mine and
I'll let you have it for $300/ month/ 3 years its yours , its in the trader
and I just got the air condition working .
Steve Clunn
> -Sam Harper
>
>
--- End Message ---
--- Begin Message ---
Sure there are several companies working on reformers. Last time I
checked, however, they ALL created pollution. Not as much as an ICE,
but still some.
I'd have to check but I'd bet a propane powered hybrid based on
something like the Insight would produce less pollution than a gasoline
reformer fuel cell setup. But that's just a guess.
On Sun, 2003-02-23 at 17:20, [EMAIL PROTECTED] wrote:
> Didn't the NASA or auto manufactures develop a reformer inorder to
> utilize the existing infrastructure for gasoline ?
> I don't know the specifics on reformers.
> Do you ?
>
> On 23 Feb 2003 18:05:29 -0700 Peter VanDerWal <[EMAIL PROTECTED]>
> writes:
> > On Sun, 2003-02-23 at 15:00, [EMAIL PROTECTED] wrote:
> > > I wonder is a 10 kw fuel cell with reformer and enough fuel
> > (gasoline,
> > > kerosine, methane, or propane) for say 500 miles would fit on a
> > small (4
> > > ft x 8 ft) trailer and how much it would cost ?? Atleast it
> > would be
> > > quiet and non polluting.
> >
> > When have they started building reformers that are non-polluting?
> >
> >
>
>
> ________________________________________________________________
> Sign Up for Juno Platinum Internet Access Today
> Only $9.95 per month!
> Visit www.juno.com
>
--
EVDL
--- End Message ---
--- Begin Message ---
----- Original Message -----
From: Rick Woodbury <[EMAIL PROTECTED]>
To: EV List List <[EMAIL PROTECTED]>
Sent: Saturday, February 22, 2003 4:10 PM
Subject: Re: EV1s waiting,rant, an' stuff; more!
> Bob Rice Wrote:
>
> > Get the Tango OUT THERE, showing what a great Station car it could
> > be. Forget the Sparrow! Tango makes it look silly, and works! What are
we
> > waiting for? Rick, how ya doin" ? Close? Betya we Listers Could raise up
> > some money, right from the heart, and bank account, to get SOMETHING
good
> > and running, in production.
> Hi Rick!
Thanks for the update below. Nice to see SOMEthing is happening!
> After an article on the Tango in the Seattle Times we received a call from
a
> passenger train car manufacturer that wants to assemble Tango so bad that
> they offered to put up the $500k for parts to build the first 10 cars as a
> project.
Wow! cars with " Body by Pullman" ? sorry I couldn't resist Or
TALGO car builders, or Pacific car? Kawasaki, just a few I could think of
off the top of my head? What a nice idea, for them, waiting for a 1000k
Subway car order to comre in from the NYCTA.
The catch is that they need 10 orders with deposits. I insisted
> that if we took deposits that they would have to be in a neutral escrow
and
> fully refundable if delivery date or quality were not met. They agreed to
> that. The only other problem is that we need to finish the present
prototype
> to Ferrari standards before we accept orders. The purchaser should know
> exactly what they are going to get as well as when they'll get it before
we
> take an order. A major automotive/aerospace engineering firm in Portland
has
> agreed to do the final fit and finish as well as complete the engineering
> for manufacture at their cost--$60k. They will commit to this figure even
if
> they spend more time than anticipated. We still need to find $60k though.
>
OK Listers are we ready for this? Rick, somebody said that they were
ready to send a 100 buck check. Can we make a meaningful amount here? A show
of hands? Many of us could spend/spare a few hundred bux, toward a REAL
Buyable EV.
> I met with Dr. Lloyd, Director of CARB last week as well as top officials
at
> CalTrans and the CHP. Things look very promising for legislative
incentives
> for the Tango. We have a lot of new material on our downloads page that
> support these changes--two studies on the GM lean machine by the
> Transportation Department at UC Berkeley and two more studies by Booze,
> Allen and Hamilton that strongly support the UNV (Ultra-Narrow Vehicle)
> concept.
> I think you could download a BUNCH of Tangoes as Station cars, to fill
in here, in the Big East, since Ford bombed out with the Think. Cuz folks
HAD Think, and would be up for another EV. You could ALWAYS find a spot at
the station a SUV hadta pass up.
Bob........thinking outloud.
> See: http://www.commutercars.com/downloads
>
> Dr. Lloyd did not think it unreasonable for the State of CA to purchase a
> high volume of Tangos to lease out to individuals in urban areas in order
to
> reduce highway and parking congestion, remove fossil fuel dependence, and
> meet the ZEV goals for the state if the state didn't have such financial
> problems. We would happily license the patent to the state for next to
> nothing just to get the ball rolling. They could go out to bid for
> manufacturing the Tangos just as they would for a light rail project.
Tangos
> could then be leased out for about $100 per month. If CA can't afford to
do
> it, is there another state that's as forward thinking that has the funds
to
> invest in a revolutionary project like this? The $9k ZEV incentive that CA
> was paying would just about pay for a high-volume produced Tango--and they
> wouldn't have to just give it away. $100 a month would be a reasonable
> return on the investment. The $2B initial investment is the only problem.
>
> That's all for now.
>
> Best wishes,
>
> Rick
>
> Rick Woodbury Phone: (509) 624-0762
> President, Commuter Cars Corporation Toll-free: (800) 468-0944
> Doubling the capacity of freeways Fax: (509) 624-1466
> Quadrupling the capacity of parking Cellular: (509) 979-1815
> Zero to 60 in under 4 seconds
> 715 E. Sprague Ave., Suite 114 Email: [EMAIL PROTECTED]
> Spokane, WA 99202 Web: http://www.commutercars.com
>
--- End Message ---
--- Begin Message ---
What a great chart! I have a Nissan Frontier so I can help you fill in
one of the missing data points.
The cargo capacity of the 1998-2002 king cabs is 1312 lbs.
Cheers.
On Sun, 2003-02-23 at 18:54, Jim Coate wrote:
> With a little web surfing this morning, I compiled a chart of the basic
> length, wheelbase, curb weight, cargo weight etc. for various pickup
> trucks - see http://www.coate.org/jim/ev/archives/truck_sizes.html
>
> Besides the good frame layout, the S-10 seems to also do well in just
> the basics of high payload for a small truck (although the Toyota does
> well for an extended cab).
>
> Also interesting is the trend of all makes to get bigger but loose cargo
> capability in recent years.
>
>
> Alan Shedd wrote:
> > Hi Jim:
> >
> > I have helped schools with S-10 and Ranger conversions. I think the S-10 is
> > a little easier to convert if you are planning to put the batteries between
> > the frame rails. (I think this is the most secure and best looking method.)
> > The frame rails have a wider spacing on the S-10 than the Ranger. On the
> > Ranger, the leaf springs are to the outside of the frame rails and the rails
> > are about 37" outside to outside (on an '83) On the S-10, the leaf springs
> > are underneath the frame rails. Also the rear suspension on the Ranger uses
> > staggered shocks - the one on the right is angled forward while the one on
> > the left is angled to the rear from the axle. Further, the differential
> > housing is not centered between the rear wheels so the drive shaft runs at
> > an angle from the back of the transmission to the differential. We were
> > able to mount 5 T-145s in the engine compartment, three T-145s turned
> > long-dimension fore and aft in a box on the left of the driveshaft in front
> > of the axle, two on the right side and five more in a box behind the axle.
> > This was a long-bed truck and there was more room behind the axle to install
> > more batteries but the school limited the voltage to 96 (ed. program rules).
> > This arrangement provided good front-rear and side-to-side weight
> > distribution.
> >
> > On an S-10 conversion, we located 2 T-145s up front. Three each in boxes on
> > each side of the drive shaft (inside the rails) in front of the axle and
> > eight in a box behind the axle. I have several photos, dimensions, and can
> > put you in touch with people at each school who can run out and measure
> > things you have questions about.
> >
> > You can get some dimensional data from service manuals for the trucks but
> > there is no substitute for looking at on and measuring it the way you want.
> > Let me know how I can help.
> >
> > -Alan
> >
> > Alan C. Shedd, P.E.
> > Advisor to Georgia's Electric Vehicle Education Program
> > (cell) 770-654-0027
> > [EMAIL PROTECTED]
> >
> > ----- Original Message -----
> > From: "Jim Coate" <[EMAIL PROTECTED]>
> > To: "EV List" <[EMAIL PROTECTED]>
> > Sent: Sunday, February 16, 2003 4:35 PM
> > Subject: pick-up truck dimensions?
> >
> > >
> > > Anyone out there who has been through a pickup truck conversion have
> > > dimensions they'd like to share?
> > >
> > > What I'm looking for are numbers like the spacing between the side
> > > rails, location of the drive shaft, location of differentail/rear axle,
> > > location of shocks, etc. ie the starting point for designing possible
> > > battery boxes.
> > >
> > > In particular I'm wondering what the difference is between long beds and
> > > short beds - is the extra length all between the cab and rear wheels, or
> > > is some of it behind the wheels? I have a '92 S-10 short bed, so any
> > > other make or model would be useful to hear about.
> > >
> > > I can go crawl around junk yards, but... why reinvent the wheel when
> > > it's cold out there :-)
> > >
> > > _________
> > > Jim Coate
> > > 1992 Chevy S-10
> > > 1970s Elec-Trak E20
> > > http://www.eeevee.com
> > >
>
>
> --
>
>
> _________
> Jim Coate
> 1992 Chevy S-10
> 1970s Elec-Trak E20
> http://www.eeevee.com
>
--
EVDL
--- End Message ---
--- Begin Message ---
The nice thing with the DCP was you could run any where from 336v down to
under 120 v and it had a dc/dc for the e meter . I called and they are not
making them right now.
----- Original Message -----
From: "Jim Coate" <[EMAIL PROTECTED]>
To: "EV List" <[EMAIL PROTECTED]>
Sent: Sunday, February 23, 2003 6:02 PM
Subject: dc/dc convertor choices?
> I had a depressing thought today... with Damon/DCP is putting on-road EV
> stuff on hold for a while, what choices are left for high(er) voltage
> dc/dc convertors? There is a rather large gap between 120v Curtis units
> (if those are even still made) and 336 volts which is the ticket into AC
> systems with the built-in dc/dc.
>
>
> _________
> Jim Coate
> 1992 Chevy S-10
> 1970s Elec-Trak E20
> http://www.eeevee.com
>
>
--- End Message ---
--- Begin Message ---
OK All,
If you had a choice, which would it be...
~13Ah class: Hawker-Genesis, or SVR in the 15 Sec discharge region
And,
What is the current pricing for the group 31's? (yellow's of course)
(I'm seeing about $126 + shipping)
Anybody done one of those 15 sec discharges on an optima 31?
Thanks in advance,
Bryan
Ps.
I like the battery management thread. I've got a home-brew'd one working
since last year equalizing a 10 string optima pack during charging and
discharging. No data management, but hey, for the price, it may become a
product as soon...as...well, you know how these things go..
--- End Message ---
--- Begin Message ---
> > -Lithium-Ion pack, say around 22kw capacity
Fire supression system?
Lock
______________________________________________________________________
Post your free ad now! http://personals.yahoo.ca
--- End Message ---
--- Begin Message ---
Message-ID: <[EMAIL PROTECTED]>
Date: Mon, 24 Feb 2003 10:11:58 -0500 (EST)
From: Lock Hughes <[EMAIL PROTECTED]>
Subject: Lithium fire control WAS:Re: Inspired Corporation's Product - Part 2
To: [EMAIL PROTECTED]
MIME-Version: 1.0
Content-Type: text/plain; charset=us-ascii
--- Sam Harper <[EMAIL PROTECTED]> wrote:
> Excuse?
> -Sam Harper
> On Sunday, February 23, 2003, at 11:41 PM, Lock Hughes wrote:
> >>> -Lithium-Ion pack, say around 22kw capacity
> > Fire supression system?
> > Lock
Hi Sam... Sorry if this is OT. Just bouncing off a current thread
in the Solar-Raycing group:
From: "S. David Lalonde <[EMAIL PROTECTED]>"
Date: Fri Feb 14, 2003 8:54 am
Subject: Re: Lithium battery safety equipment
Might I also suggest a large bucket of Lith-X to be carried by the
support crew? A quick release or ejection system would be very
useful to employ for teams with Lithium based batteries. Could save
a lot of the time and money that was spent on building the cars.
One caveat to using Lith-X (and perhaps even the D-class
extinguishers) is that it is conductive and could possibly short the
cells. If they are already burning then maybe that is not your
primary concern.
A lot of water on a small fire of burning Li-ion or Li-polymer cells
will help to reduce the heat and limit the spread of the fire but
will do little to nothing to put out the fire. However, I would not
characterize a burning solar car battery pack as a 'small' fire. A
small fire would be a few cells. Also, where would you find lots of
water during a race? Water will react with Lithium metal and ions
to form hydrogen gas and if it is in an enclosed environment that
could generate a potentially explosive atmosphere. Outside it
should not be a problem, if the pack has been removed from the
vehicle. However, most of the fire will be from plastic and
electrolyte burning, and very little due to reacting Lithium.
Yes, dirt is a good alternative if graphite or Lith-X is not handy.
Separate the pack from the vehicle, cover it as quickly as possible
with the Lith-X/dirt/class-D then get far away and let it burn
itself out. Warn others about the hazard and do not let them
approach the fire. Depending on the construction of the pack there
is a significant potential for a dangerous explosion. An open,
unsealed pack design is best, and individual cells should have
effective burst pressure relief valves in the headers.
How much do the teams look at the safety test results of individual
cells? Do the Sun-Rayce regulations include any safety requirements
for individual cells, such as having to pass the UL1642 series of
safety tests?
I have personally performed UL1642 safety tests on high power
cylindrical Li-ion cells. During fire exposure tests they generate
flames like little rocket engines, shooting out of the headers up to
about 3 feet, and under certain circumstances they can explode,
expelling the jelly-roll and header, and sometimes ripping apart the
can.
David
S. David Lalonde
Soopah Packs @ http://www.soopah.com/
E-mail: davidl @ soopah.com
--- In [EMAIL PROTECTED], "Martin Koebler"
<[EMAIL PROTECTED]> wrote:
>
> I would suggest have a shovel with you at all times that you can
bury your
> pack in dirt if they catch on fire. We had FIVE, 4ft high class D
fire
> extinguishers that was all used up that didn't stop our fire in
our vehicle
> that we once had. Only reducing the oxygen flow to the cells by
covering
> them in dirt really helped.
>
> It's also good to think how to get batteries out of the vehicle,
such as
> being able to turn your vehicle upside down to save your car
body. Avoid
> securing the batteries too tightly with beams and metal bars etc...
>
> The best thing is prevent something like that to happen in the
first place
> by:
>
> 1) Have a good balance pack that you can monitor the cells.
> 2) Jumper bad cells if they start to drift on the upper or lower
end.
> 3) Have over voltage cut-off protection on both regen from the
motor
> controller and MPPT's.
> 4) Don't be fooled measuring cells in parallel, individual cells by
> themselves could have a different "true" voltage.
>
> In my opinion, one fire extinguisher isn't going to do you much
good if the
> pack goes off like fire works. Don't cut corners on safety issues
with LI
> cells.
>
> Martin Koebler
> Solar Motions Project Leader
> http://www.solarmotions.com
>
> -----Original Message-----
> From: Formula Sun - Team HQ [mailto:[EMAIL PROTECTED]
> Sent: Thursday, February 13, 2003 11:08 AM
> To: [EMAIL PROTECTED]
> Subject: [Solar-Raycing] Lithium battery safety equipment
>
> Solar Car Teams --
>
> For those of you who are working with Lithium batteries, please
note that
> you will need a Class D fire extinguisher as part of your
battery safety
> equipment. (This will be checked during Scrutineering at the
Support
> Vehicle station. Scrutineering check lists are online.) You
may want to
> have one of the extinguishers in your lab now if you are working
with the
> batteries.
>
> If you believe that your batteries require another type of
extinguisher,
> please send a description of the safety equipment that you plan
to bring
> and why by 4/1/03 (send to [EMAIL PROTECTED]). Please note that while
> the battery inspector will review this information, you may
still be
> required to bring a Class D extinguisher.
>
> Please contact me if you have any questions.
>
> Thank you,
> Kate von Reis
> FORMULA SUN GROUP OF EVENTS
> Team Information
> tel: 800-606-8881 / 509-968-3601
> em: [EMAIL PROTECTED]
> web: www.formulasun.org
______________________________________________________________________
Post your free ad now! http://personals.yahoo.ca
--- End Message ---
