Nissan Tests 48-kWh LEAF

TomT said:

Until I had some VERY concrete evidence that temperature degradation was truly no longer an issue, I'd not pay any more... "Fool me once... (tm)"

KJD said:

What would you be willing to pay for a LEAF with a 36 or 48kWh pack ?

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Well... Two of the big reasons for temperature degradation are:

1. Current draw vs Total Capacity

2. Rate of Charge.

If you blast down the freeway for 30 minutes at 75 mph... your current draw with be a Large Percentage of the total available power
and Battery Temperature Goes UP.

If you Quick Charge at a very high percentage of battery capacity say 20 KwH in 30 Minutes then: Battery Temperature Goes UP.

Now.. double the battery back capacity and do the same thing.

In both cases the Battery Temperature Rise will be lower - and less detrimental - because the percent of capacity draw or charge is Half
while the same thing is accomplished.

this doesn't take the place of chemical or physical changes in the battery construction needed to make them play in Phoenix in July...
but it will HELP. and in your SoCal zone and driving environment it will help a LOT. Also, for the same use, the number of charge cycles is also cut in half,
and the number of deep discharges and over 80% charges can effectively become zero... and that really improves longevity when the battery operates in that 20-60 % sweet spot. Notice I am NOT saying anything about the nutcake 600-700 lbs additional weight added to a Leaf... which isn't going to fly. :ugeek:

I think of the Leaf as the VW Bug of this century.

One of the things that made the bug work so simply was Air Cooling.

While in motion there is a fine opportunity to use Ram Air ducted through the battery pack to achieve
a good degree of cooling.

That can be passive or blower assisted... without any large energy outlay. A squirrel cage motor is quiet efficient at providing
positive pressurization and moving a good number of CFI . Given the small volume.. pressure is the answer. There are already 3 temp sensors
so this isn't hard to manage.

---

There seems to be some room between the top of the battery case and the underside of the vehicle floor.
this might be suitable for a liquid heat sink,, visualize something like a flat plate solar collector.. tubes in contact with
metal sheet.. or a thin bladder or envelope of liquid.. pipe the hot water out to a radiator, and the cooled water back through
in a closed loop. add a fan and some more ram airflow...

none of this is rocket science.. but I prefer the aircooled method because it is Light, Cheap, Simple. And because it doesn't interfere
with the basic construction of the existing battery pack. Nissan doesn't want to change that - rightly- because they are trying to
achieve Economics of Scale by producing large numbers of batteries based on the existing mechanical form internal and external.

-- If there was ever a worthy Shade Tree DIY Leaf Improvement Project.. it would be working up a simple auxiliary air cooling system
for early Leafs.- A look under the car ( try IHS crash test video) shows what can be done.

Of course your Leaf might sprout an Exhaust Pipe ! :lol: :lol:

The Human ( read IDIOT) Factor is the wild card that eludes the Engineers who try to emulate battery life.

they wouldn't dream of emulating a drunken cart driver whipping a donkey and feeding him rotten food less often than he
should.

but that is how people really behave.

Just as they will try to run ICE cars without oil, or water.

So, I don't blame them when Dr Donkey who really wants his leaf to be a Tesla, beats the crap out of the battery,
never mind what it says in the manual. The manual is the last thing to wear out in a car. Absolutely the last thing.

If the drivers would 'cool it'
Nissan wouldn't have too ! Look at the construction of a Volt Battery.. if you want to see a Nightmare of water cooled construction !

What I expect is that new chemistry maybe even cathode structure changes will find thei r way into the Leaf configuration battery over and over , but it won't change in structural or conceptual aspects for a decade... because it needs to show a profit.. since Nissan Bet The Farm on Electrics.

Someday 2011's will roll around with some pretty evolved batteries... if the owner wants to spend the money.

Think VW beetle.

The beetle sucked but the engine was interesting.

Its a pity that batteries are such an issue with vehicles because electric is by far the best.

I'm thinking that for future long distance travel, cars will need to get their electric energy externally.
It's likely that all major highways will be rigged to provide that energy while batteries will provide the off highway power.

Certainly the current modus operandi will need to evolve into something more useable.

Zurc.

Unless they changed the units on GIDS, 511 is a 42 kWh battery, not 48.
But 42 is what the rumors were mostly saying for the larger pack next generation LEAF.

TimLee said:

Unless they changed the units on GIDS, 511 is a 42 kWh battery, not 48.
But 42 is what the rumors were mostly saying for the larger pack next generation LEAF.

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What are you referring to? Where did you get 511 from?

DanCar said:

TimLee said:

Unless they changed the units on GIDS, 511 is a 42 kWh battery, not 48.
But 42 is what the rumors were mostly saying for the larger pack next generation LEAF.

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What are you referring to? Where did you get 511 from?

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There was a post in the thread yesterday where someone in Ontario claimed they had used LEAF Spy on one of the test cars.
Photo showed 511.
But the post disappeared.

TimLee said:

There was a post in the thread yesterday where someone in Ontario claimed they had used LEAF Spy on one of the test cars. Photo showed 511. But the post dissppeared.

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Cool. That roughly comes out to 147 mile range. In line with previous rumor of 150 mile car. 42 kWh * (84 mile range / 24 kWH) = 147 mile range.
If they are testing a car now, any guesses when we will be able to buy it? Where is the beta sign up sheet?

I think that was a joke post, showing an anomaly in LeafSpy?

Berlino, Is that spy pro reading for real or did you adjust it from a regular LEAF?

If it's real was it a regular looking LEAF?
Did it have the rear trunk filled with batteries or ?

TimLee said:

Unless they changed the units on GIDS, 511 is a 42 kWh battery, not 48.
But 42 is what the rumors were mostly saying for the larger pack next generation LEAF.

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need more explanation how you get to 42 kwh from 511 GIDs. if we take GIDs to be 80 wh that is 40.88 available from a pack of 43.222 kwh using same percentage as the current pack (22.7 from 24 kwh) which is logical of same cells are used.

But if we take another accepted number of 74 wh/GID. that is only 37.814 kwh available or a 39.6 kwh pack

or am I missing something? which is possible. haven't been to this thread in a long time and don't know where the 511 GIDs came from

24kWh/292 GIDs = .0821918
.0821918 X 511 GIDs = 42 kWh
That's my guess.

The 511 reading was bogus. See page 2 of this thread.

Berlino said:

I was just joking. When I take ODBII readings immediately after charging to 80%, I sometimes get amusing out-of-bounds readings from LEAF Spy, it just so happened that one of them corresponded with a 48 kWh LEAF.

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keydiver said:

24kWh/292 GIDs = .0821918
.0821918 X 511 GIDs = 42 kWh
That's my guess.

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Yes, was prorated on GIDS.
Missed that it was a joke :?

keydiver said:

24kWh/292 GIDs = .0821918
.0821918 X 511 GIDs = 42 kWh
That's my guess.

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sorry but your numbers are invalid. you are combining pack capacity with usable GIDs.

try usable pack or "kwh available" on LEAF Spy on a full charge with the 292

I hope Nissan decides to add the ability to precondition the battery (aka bring it up to optimal battery temperature) while plugged in. In cold weather below 25F I manage only about 40 miles on a full charge before I hit LBW. Also having little or no regen in winter really sucks.

elmobob said:

I hope Nissan decides to add the ability to precondition the battery (aka bring it up to optimal battery temperature) while plugged in. In cold weather below 25F I manage only about 40 miles on a full charge before I hit LBW. Also having little or no regen in winter really sucks.

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More importently a 12Kw charger! I wouldn't buy one with out a larger charger bad enough it takes 4H when cold out to charge the 24Kw pack, like hell I'll sit around 8+ waiting for it to charge!!!

Larger charger then bigger battery!

XeonPony said:

elmobob said:

I hope Nissan decides to add the ability to precondition the battery (aka bring it up to optimal battery temperature) while plugged in. In cold weather below 25F I manage only about 40 miles on a full charge before I hit LBW. Also having little or no regen in winter really sucks.

Click to expand...

More importently a 12Kw charger! I wouldn't buy one with out a larger charger bad enough it takes 4H when cold out to charge the 24Kw pack, like hell I'll sit around 8+ waiting for it to charge!!!

Larger charger then bigger battery!

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That would require a 60A breaker, not so likely in most homes nor a good choice for an automake. 9kw would be the max likely and that would do a full charge in about 5 hours, same as the RAV4

XeonPony said:

elmobob said:

I hope Nissan decides to add the ability to precondition the battery (aka bring it up to optimal battery temperature) while plugged in. In cold weather below 25F I manage only about 40 miles on a full charge before I hit LBW. Also having little or no regen in winter really sucks.

Click to expand...

More importently a 12Kw charger! I wouldn't buy one with out a larger charger bad enough it takes 4H when cold out to charge the 24Kw pack, like hell I'll sit around 8+ waiting for it to charge!!!

Larger charger then bigger battery!

Click to expand...

Larger batteries make the charging problem easier. If you had a 10,000kWh battery, you would need a charger large enough for the average usage, not the peak daily usage.

EVDRIVER said:

XeonPony said:

elmobob said:

I hope Nissan decides to add the ability to precondition the battery (aka bring it up to optimal battery temperature) while plugged in. In cold weather below 25F I manage only about 40 miles on a full charge before I hit LBW. Also having little or no regen in winter really sucks.

Click to expand...

More importently a 12Kw charger! I wouldn't buy one with out a larger charger bad enough it takes 4H when cold out to charge the 24Kw pack, like hell I'll sit around 8+ waiting for it to charge!!!

Larger charger then bigger battery!

Click to expand...

That would require a 60A breaker, not so likely in most homes nor a good choice for an automake. 9kw would be the max likely and that would do a full charge in about 5 hours, same as the RAV4

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No it wouldn't

I said charger not evse.

Standard 40 amp 240 is fine in the home, time is not an issue here, it is the on road L2, here in Canada most every one is 70 to 90 amps.

A 12kw capable charger would make the current 24Kwh pack super use full. 1H top ups would give a significant range boost out on the road, and for full charges be 2 to 3 h (Factoring in balancing) with a 48KWh pack it becomes required to get any use full range extensions for the mileage most would want.

At home a standard 6Kw unit would be, well standard, as at home you tend to be, well, at home for the night making the 6kw more then adequate.

Adding to the fact I stated that the smallest L2 in Canada universally are no less then 70AMp (Average being 80 to 90A) (I'd wager it is true in the states as well) the 12Kw capable charger is perfectly logical in preceding a larger battery.