EVLN: Hoo boy> How Far Can You Push an EV Battery?

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EVLN: Hoo boy> How Far Can You Push an EV Battery?

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https://jalopnik.com/just-how-far-can-you-push-an-electric-car-battery-1827929360
Just How Far Can You Push an Electric Car Battery?
Photo:
Hazel Southwell

[images  
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Photo: Williams

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Photo: Williams

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Photo: Getty Images

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Photo: Getty Images


video
https://www.youtube.com/watch?v=vG1VPss4LKI
Huge Crash In Formula E's First Ever Race! - Prost vs Heidfeld Accident
]

It weighs 440 pounds, it endures temperatures up to 140 degrees, and it’s
been on a four-year stint that amounts to the same distance as going around
the earth and then some. Not my luggage, despite what you might assume, but
the absolute unit at the back of the first generation of Formula E race
cars. Slapping the roof of this bad boy would earn you a disapproving look
from the engineers but you can fit 33,865 miles of racing without a single
failure inside it.

And the thing that’s extraordinary is it hasn’t changed since 2014.

These chunky boys have been a permanent feature of the Formula E paddock—not
just the 40 inside the cars, but spares being wheeled round that you can get
a good look at. They stand out because even on a flatbed trolley they come
up to my waist, and are roughly the dimensions of a phone box, width-wise.

They had their swan song in New York a few weekends ago. The final race of
Generation 1, the last time these troopers were going to power the cars that
were built around them. The final of around 50 full charge cycles each
undertakes during a season, blinking down to 1 and then zero percent for the
last time.

Next year’s season, Formula E’s fifth, will see an updated battery powering
the Gen 2 cars; only 110 pounds heavier, the speed of advancement since 2014
means it will go the race distance with no car swap. It almost doubles the
energy storage of the first generation, dealing with 66 percent higher
output and 100 percent higher regeneration than these were originally built
for.

But the first effort shouldn’t go out unnoticed. It’s easy to get excited
about the future, but the case could be made that these batteries were the
unsung heroes of a rising global series, one that moves along with the race
toward better, faster, longer-lasting batteries for everything from laptops
to cars to e-cigarettes—the future of power itself.

When the battery was designed by Williams Advanced Engineering back in 2014,
no one really knew if you could make a viable, believable electric race car.
At the time, Formula One was still getting its head around having its own,
relatively tiny batteries (or “energy stores” in case your masculinity was
impinged by the concept of lithium-ion) and the idea of trying to bang
something round at race-pace on electricity alone was pretty buck wild.

We’ve sort of forgotten that in the interim because it—slightly
unexpectedly—worked. Forty cars using forty batteries went out at race one
and every Eprix since.

They’ve got prospects beyond that, but in all the champagne and sponsorship,
there’s an integral part of the cars that’s never got up on the podium. The
batteries have stood fast for four seasons, despite doubts they could even
work at the time.

Doing What’s Never Been Done

There’ve only ever been two on-track battery failures, and none for the last
two seasons. With only one allocated battery per car per season that’s a lot
of mileage, before you even account for the constant charging and
discharging they undergo.

From the outset, the spec of the battery was thus: 28kWh of lithium ion good
times, discharging into and being charged from the powertrain of the cars
during race conditions. That’s a hefty 45kWh (or so) less than the most
basic Tesla, because the idea of Formula E is that it tests the kind of tech
an average hatchback is going to work with, while extracting supercar-grade
performance.

In fact it’s actually got less storage capacity than a 2016 Nissan Leaf,
which rolls around with a mere 30kWh. The thing is, Formula E batteries
aren’t going to output the charge it takes to tootle you round a journey to
the supermarket and back; they’re going to slam it to the left, shake it to
the right and probably lift and coast a bit on the straights depending on
regenerative temperatures.

The life of a Formula E battery makes a road EV’s look trivial; smacked
sideways into a barrier at 10 a.m.? Better be ready for qualifying at 12,
kid. And the temperatures—they’re limited to a relatively safe 60C (140
degrees F) which Williams have confirmed to me they haven’t exceeded, but
just for reference that’s five degrees celsius hotter than you need to fry
an egg.

The Formula E battery could look a Tesla in the eyes and say “do it then,”
and the Tesla would quietly overheat.

And the Formula E batteries are still going, in not just the race trim they
were built for but at substantially higher performance.

Plenteous protein options for recovering drivers aside, these are some
steamy hot boys that mostly race in temperatures above 80 degrees F
(Marrakesh provided a strange rarity with snow over the Sahara last season)
and are brutally cooled with dry ice in between rapid-fire sessions.

Which makes it all the more extraordinary that somehow the same unit has
persisted for four years with only minor upgrades. Back when there was a lot
of cynicism about whether a battery could survive racing conditions—or even
hold enough power to go the distance.

Batteries Are Actually Badass

There are people out there who straight up think if you crash an electric
car you’ll be flooded with battery acid. Hoo boy, my friends; clearly none
of them are Formula E viewers, where we routinely beat the cars around like
they’re volleyballs and this is an extreme beach grudge match.

Nick Heidfeld has a pretty good idea about this, having been hurled into the
air along with the best part of a tonne of machinery:

Nothing happened. Nick walked out of the car to have what looked like a
fairly energetic word with Nico Prost; the battery didn’t explode or catch
fire or fail, the car didn’t electrify, the survival cell wasn’t breached
despite a 200 kilogram thing rattling around in the back of it as it did an
impressive triple pike.

Looking at that 2014 crash it seems bonkers—not just because how the hell
did Nick just get out of that but because the cars, the feel of the races,
has changed so much since then.

That first race in Beijing was 53 miles. Not the shortest in the first
season, which goes to Monaco at a mere 42 miles. At the time, the maximum
race output was 150kW and the maximum regeneration (energy shoved back into
the battery, recovered under braking) was a mere 100kW.

Both of those numbers are, again, quite modest for an electric car. A Tesla
Model S, say, can output 311kW, for awhile. When the battery starts to reach
the limits of its operating window, temperature-wise, the car will halve the
available power output whereas a Formula E car is expected to continue to
perform throughout the race, with the driver managing battery temperatures
as much as possible.

Which makes it all the more extraordinary that the first-generation battery
didn’t just service races of under 90km (56 miles) at low output and
regeneration but went on to first increase race output (qualifying has
always been higher) to 170kW in season two, then up regeneration by 50
percent in season three to 150kW followed by another race output increase in
season four to 180kW.

At the same time, the race length kept extending—cars that had struggled to
manage the power for 50 miles or so were pushed to over 68 miles in Berlin
this year. Different powertrains, yes, but the same battery unit.

Second (No Half) Life

With battery lifetime and battery capacity such concerns in electric vehicle
development, the generation one unit has to be held up as something
extraordinary. The common wisdom is: range extension is possible, with
better battery management and that output and regenerative extension is also
possible but not both at the same time.

Especially not when, although the battery maker could take data from and
advise teams they weren’t actually in control of the way the powertrains
linking to their units were built or used. Imagine crafting, say, a perfect
cake and then handing it over to a bunch of other people to bake. Only it’s
20 different people and they’re all insisting on doing it live on television
using only straightening tongs while wearing rollerskates.

This battery’s gone racing more than 1,200 times and covered over 33,865
miles since the last on-track failure, back in 2015. It’s gone several times
that in transit, across continents and on boats and planes, been frozen,
been pushed to its upper heat limit. Eight thousand full discharges at
circuits, which means 8,000 full charges (and then some, with regeneration)
and these chunky guys are still going.

That’s a big deal. There’s a presumed lack of secondhand market for electric
vehicles because battery degradation is supposed to be so severe. You could
say “oh, well Formula E just throw them out after every race so of course
they’re still going” but here’s the thing: they don’t.

Drivers are only allowed one battery per car per season. There’s a
possibility to change it under one, 30-to-60 day forward-planned “joker”
option but unsurprisingly, most teams don’t take that given the need to book
in an FIA appointment for re-inspection. These aren’t throwaway items and
although they’re not used every day, the race days are massively more
intensive than any normal usage would ever push a battery to.

Battery lifespan and durability is no small part of the viability of
electric vehicles as a whole. About half of the carbon involved in
manufacturing an EV is on the battery which then immediately starts to even
out, on most European energy grids, due to being able to use renewables for
charging. Naysayers are quick to point out that that will be neutralized or
even worsened, compared to an internal combustion vehicle, if batteries need
regular replacement.

Using Formula E as the Petri dish it’s supposed to be for the electric car
industry, this very much indicates they won’t. A well-treated Nissan or NIO
or BMWi battery, most of which are guaranteed for the best part of a decade
in any case, could even have its life extended through the sort of simple
cooling and bumper updates Williams made in 2016.

Having mastered the challenge of letting drivers loose on their carefully
crafted tech in Formula E, Willams is now going on to electrify World
Rallycross. Just in case hurling batteries at concrete wasn’t enough,
they’re now leaving that game to McLaren and moving on to shaking batteries
around like they’re trying to make a lithium-ion frappuccino. Extra large.

Battery limitations are cited as major concerns around electric vehicles, to
the point that people really thought this was going to stop Formula E, was
going to prevent the racing. It hasn’t. It’s pointless to speculate how much
longer the first-gen batteries could have carried on, if the chassis wasn’t
changing but there’s no doubt it was still getting the job done by the end
of season four, lap records set on every track.

Yes, they’re big for 28kWh of power. Yes, these extra-large energy stores
would dwarf your coffee table and you’re not likely to get far trying to
carry one on foot. But if these first four seasons were the test of whether
lithium-ion was tough enough to do a reliable job in vehicles, then they’ve
passed with extra credit.
[© jalopnik.com]


+
http://www.machiningnews.com/2018/07/the-battery-the-heart-of-an-electric-vehicle/
The battery: the heart of an electric vehicle
July 26, 2018 Battery technology will play a major role in product
development across all sectors of the automotive industry with the continual
drive to reduce vehicle emissions ...
http://www.machiningnews.com/wp-content/uploads/2018/07/Battery_Content.jpg




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