Re: Q:NEDRA on batteries..

[Bill Dube <billdube@killacycle.com>]

>> ...battery boxes will deform during a collision... If the batteries
>> are flooded, acid will go flying. If they are AGM or TMF type, only
>> a few drops will get loose. Virtually no acid spilled is safer than
>> lots of acid spilled.
>
>A flooded battery is not a washtub full of acid. It is a closed
>polypropylene box, with many separate compartments. Have you seen
>flooded batteries after crashes? Car manufacturers usually locate them
>right up front, with no protection. The case is often terribly deformed,
>yet it still holds acid. Even if it leaks, it is usually only 1 or 2
>cells that get ruptured; not every cell. You're talking about a Coke
>can's worth of acid; not gallons.

	An EV with flooded batteries has gallons of acid. 

	I remember buying a flooded battery at Target for my ICE car. The young
clerk brought the battery from the storeroom to the check-out and foolishly
placed the box on it's side. After just a minute or two, enough acid had
leaked out of the battery and through the cardboard box to make a big
puddle on the counter. Imagine 20 large flooded batteries in an EV on it's
side. Gallons of acid will flow out of the car.

	I was standing nearby in a Checker Auto Parts parking lot when a fellow
blew up a flooded battery. Acid rained down everywhere. He was soaked to
the skin with acid. The entire engine compartment was covered with acid. It
was a lot more than a cupful. 

>ICE dragsters contain fuel, oil, and coolants that frequently spill.
>They manage to set rules to limit leakage and clean up the spills
>adequately, without resorting to banning them outright. Are you saying
>that flooded batteries are intrinsically more dangerous than gasoline,
>oil, or antifreeze?

	There is no alternative to having fuel, oil, and coolants in an ICE
dragster. (Actually, many purpose-built dragsters have no coolant.) If
there were a practical alternative, they would ban the use of these fluids.
In the faster machines, the amount of fuel is limited, and the driver wears
a flame suit. Also, there are strict rules about separating the driver's
compartment from all of these fluids.

	In a purpose-built dragster, flooded batteries would offer no cost
reduction, would reduce performance, and decrease safety. For the same
reason that they don't allow cast-iron flywheels in drag racing, they don't
allow flooded batteries in some types of vehicles.

	Flooded batteries will likely always be allowed in slow, daily-driver type
EVs that want to have fun taking a run down the strip. They will be
traveling typical highway speeds and will have slow ETs. However, in
purpose-built drag racing EVs, flooded batteries are banned in certain
types of vehicles. These same vehicles typically are required to have
roll-bars or roll cages, driveshaft loops, special seat belts, and special
protective clothing for the driver. Flooded batteries don't make sense in
this context.

	For a dragster, (even a Jr. dragster) you have to buy an approved helmet
for several hundred dollars. You also have to construct a roll cage and put
in approved seat belts. This costs quite a bit of money. You spend this
money to improve safety. No doubt, you could save money and buy a cheaper,
un-approved helmet and only reduce safety "a little." After all, you are
surrounded by a roll cage and held in place by an expensive safety harness.
Why do you need an expensive helmet too? If the rules were not in place for
the specification of the helmet, some foolish folks would take this
approach. They would wear a bicycle helmet to save money and to "save weight."

	>
>Sure, batteries fail (often dramatically) when racing. But when it
>blows, you're talking about one battery (usually one cell); not a whole
>pack. If it blew because the cell went dead, remember that means the
>electrolyte is largely water. Most battery failure modes apply just as
>well to sealed as floodeds.

	In dragstrip battery failures, the entire top or side of the battery
typically is blown off. Other near-by batteries are often damaged by the
plasma, molten lead, and the force of the expanding battery. One cell
fails, but it takes some of it's neighbors with it. Plain water is not what
flows out of a blow-up flooded battery. Acid sprays everywhere. It is not
the same as a typical battery failure in a daily driver. 

>
>> You can't charge flooded batteries in 15 minutes.
>
>The Norvik Minitcharger and Aerovironment ABC-150 (both 150 kw charger)
>are fast-charging flooded fork lift batteries in these time frames right
>now. The evidence is that it saves the cost of a second battery pack
>(recharge during breaks instead of swapping batteries every shift), and
>may extend battery life.

	Not fifteen minutes or less for a fully-discharged pack of flooded
batteries. Get real. The pack would become a molten sizzling blob.

>
>> You cannot use flooded batteries in an open car (like a dragster) or a
>> motorcycle.
>
>Why not, if the batteries are in a second case to contain any acid
>spills? 

	You can't because the NHRA won't allow it. 

>Isn't it the results that count, not the method used to achieve
>it?

	There is no performance advantage to flooded batteries. For a given level
of performance, there is no cost advantage to flooded batteries. Flooded
batteries are not as safe as AGM or TMF batteries. Track damage and
clean-up delay are more likely with flooded batteries. There is absolutely
no reason to allow them outside of a "daily driver" class.

	Also, who is going to design and inspect this "secondary containment"
system? If you went through the trouble to put together a specification for
the rulebook, how would the inspector be sure that the container passed the
spec? You would probably have to require that the secondary containment be
constructed by a certified shop and have a placard identifying it. This
would be very expensive indeed. No one would take this route. It would be a
complete waste of time and money.


Bill Dube'  billdube@killacycle.com
check my website at:
http://www.killacycle.com