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The problem is likely Nissan's air cooling system used for the Leaf's battery

The Nissan Leaf is a top player in the electric vehicle (EV) industry, but one major issue that sometimes plagues these vehicles is the battery -- and the Leaf's battey seems to be taking a lot of heat.

Leaf owners in Arizona have recently complained that their EVs are losing significant capacity in the desert's hot heat. In fact, Arizona Leaf drivers Scott Yarosh and Mason Convey have both testified to this claim.

"When I first purchased the vehicle, I could drive to and from work on a single charge, approximately 90 miles round trip," said Yarosh. "[Now] I can drive approximately 44 miles on this without having to stop and charge."

Both owners said they've lost about 30 percent of their battery capacity since purchasing their vehicles. Even when their batteries are fully charged, two to three of the 12 lights on their battery capacity gauge are out.

Both owners are very meticulous about how they care for their Leafs. There is absolutely no sign of abuse, as both were able to produce dealership service records with high marks.

"We want to learn more about what's going on, but it's something we've just been made aware of, and we don't have any conclusions yet," said Perry.

The problem is likely Nissan's air cooling system used for the Leaf's battery. Tesla CEO Elon Musk even predicted that Nissan's cooling system would fail the Leaf at some point back in August of 2010.


Musk said that Nissan's Leaf employed a cheaper air cooling system that would make its battery temperatures jump "all over the place," where cold temperatures would degrade the battery while hot temperatures would shut it down. Tesla, on the other hand, uses a high-end liquid heating/cooling thermal management solution.

But for those who are still avid Leaf fans, there's great news if you live in California or Washington. Dealerships in these two states are cutting about $5,000 off the price tag for a new 2012 Nissan Leaf. The MSRP is usually $37,250, but with the $7,500 federal tax credit, the $2,500 California clean-vehicle purchase rebate, and now the additional $5,000 off, the price for a brand-new 2012 Leaf is only about $23,000.

Sources: CBS 5, Green Car Reports



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RE: What a deal!
By EricMartello on 7/20/2012 7:38:06 PM , Rating: 2
Nice, but consider this:

Standard 40 mile range under IDEAL conditions. Oh look, it's winter. The temps are now below zero.

Full-Charge Cold Weather EV Range: ~25 MPH

Why? Because the batteries discharge faster under their rated loads when below the low side of their operating range. Net result = reduced range and possibly reduce battery life due to "deep cycling".

Winter is over, now it's summer. Man it's 100 degrees today, better top of my EV and head to the beach. Oh..wait...it's so hot that the battery's effective capacity has been slashed by 40% or more. I can barely make it to the Wawa around the corner and back.

My point is that BATTERY TECH is preventing EV from becoming a practical commuter vehicle when compared to vehicles powered by chemical fuels. There is no comparison to anyone with a rational and logical mind.

Standard gasoline and diesel cars:

- Cost less.
- Less complex, easier to maintain.
- Far more reliable and predictable in a variety of conditions.
- Still economical if you go for something like the Chevy Cruze Eco or any of the VW/Audi TDI models.

EVs do not "reduce carbon" so if you were going to say "But, they don't spew out toxic gases" guess again. Electricity production is still mainly fueled by coal. If most people were driving EVs and charging them daily, the load on the grid would increase proportionately and so would the emissions. Quite frankly, the tailpipe emissions from a modern car are much cleaner than what comes out of a coal-fired power plant. Add to this that electricity would also become more expensive across the board due to increased demand.

By the way, you can real world examples of this on a small scale at any electric R/C car track. Ask the owners how much they spend on electricity to run multiple charging stations to charge little 3300 mAH battery packs...it's not as cheap as you think it would be. Battery charging is one of the most INEFFICIENT uses of electricity we have - far worse than incandescent light bulbs.

Ask the people racing their R/C cars how an overheated battery pack can't hold a charge or can actually go "dead" if they attempt to charge it while it's hot. These are both NiMH and Lithium Polymer (LiPo) battery packs - most EVs are using NiMH, with LiPo being lighter and having a higher power density...as well as a tendency to explode if not kept within tight tolerances...so we're not seeing EVs with LiPo batteries any time soon.


RE: What a deal!
By JKflipflop98 on 7/20/2012 9:28:45 PM , Rating: 2
You're mostly correct, however electric cars are less complex and easier to maintain than an internal combustion engine.


RE: What a deal!
By Dr. Kenneth Noisewater on 7/21/2012 10:56:38 AM , Rating: 2
quote:
- Less complex, easier to maintain.
- Far more reliable and predictable in a variety of conditions.


Wrong. Electric motors are much simpler and lighter than otto or diesel cycle engines. Also, electronic components are typically far more reliable than mechanical components. How predictable is a bad tank of gas that clogs the fuel filter, or a bad batch of diesel requiring a fuel rail purge, or a snapped serpentine belt that causes the alternator to stop spinning, or a snapped timing belt or chain that causes your valve heads to crash against the cylinders?


RE: What a deal!
By EricMartello on 7/21/2012 6:58:56 PM , Rating: 2
Electric motors are simpler conceptually. The EV powertrain is not simpler than the typical mechanical powertrain in a standard gas or diesel vehicle in terms of real world troubleshooting and maintenance. The motor itself is controlled by electronics and electronics can and do fail.

If you purchase your fuel from a busy gas station the chances of a "bad batch" are virtually non-existent. In fact I've NEVER had this happen to me and I log thousands of cross-country miles per year for my rally racing events.

Even if you did get a batch of fuel that is so bad that it managed to clog the fuel filter...diagnosing the problem and replacing the fuel filter is something just about any mechanic anywhere in the country can do in half an hour.

A snapped belt is just as easy to fix, and a timing belt/chain is a bit more involved but still a relatively easy fix. None of these would leave you stranded waiting for a part from the manufacturer, or require you to go to an "authorized dealer" for repair.

The examples you cited have nothing to do with the engine's implemented complexity. They are routine maintenance and potential failure issues that a small portion of people may experience. I've never had any of the above happen to me, but then again I take good care of my vehicles by myself.

If an EV motor stops working it could be any number of potential issues, most of them will be electronic in nature which require specific and proprietary tools to diagnose and repair. The car will likely require specially ordered parts to repair and the availability of said parts is going to be limited...i.e. not at your local Napa shop.

Electric motors are not lighter than their gas/diesel fuel-powered counterparts of similar power ratings. Most hybrid and EV motors are in the 40-60 HP range - the 40-60 HP range can be serviced by a gas engine with 600cc displacement weighing in around 150 lbs. A small block V8 can weigh below 500 LBS and produce in excess of 500 HP. When it comes to power to weight ratios, electric motors cannot compete. Oh, and don't forget to add the weight of the battery pack in when totaling up the weights. Figure 100-200 lbs for batteries depending on the vehicle.

On last thing to note is that people often talk about electric motors having full torque at 0 RPM - true...but if you look at a dyno of the specific electric motors used in hybrids (PMSM) the torque curve plummets as the engine speed (RPM) increases. That's the tradeoff, otherwise it would be high torque with peak RPM under 2,000 and prohibitively high weights. Pretty much fail in terms of performance when compared to a decent V6 or V8 that maintains its full torque across its power band and can spin up to 7,000 RPM or more.


RE: What a deal!
By Richard875yh5 on 7/24/2012 12:24:19 PM , Rating: 2
I can tell you as an EE that electric motors can run 24/7 for decades and I have seen many go that far. You can not tell me an ICE can do that!


RE: What a deal!
By EricMartello on 7/24/2012 6:24:00 PM , Rating: 2
That's a very ambiguous statement, and even if it were more specific it would be irrelevant because cars are not driven 24/7. They are driven periodically.


RE: What a deal!
By Richard875yh5 on 7/25/2012 6:43:18 PM , Rating: 2
is

Your reasoning does not make sense. You can put a spin on my remark by saying it is ambiguous. There is nothing ambiguous about reliability.


RE: What a deal!
By EricMartello on 7/26/2012 8:47:30 PM , Rating: 2
Stating that an electric motor can run 24/7 without specifying the type of motor, it's environmental conditions and its purpose makes it ambiguous - especially since we are talking about cars here.

As far as cars go there are plenty of them which do hundreds of thousands of miles and still keep going - taxis, police cars.

To be more general, industrial diesel engines can run non-stop reliably for decades in construction, farm and marine equipment - all harsh environments. Many of these are with minimal maintenance due to tight operating budgets.


RE: What a deal!
By lexluthermiester on 7/23/2012 11:08:48 PM , Rating: 2
EricMartello's points cover most of what I was thinking except two.

1. The timing belt issue. Almost all cars made in the passed 15 years have zero interference valves. IE, they never come or can come in direct contact with the cylinder heads. A broken timing belt requires only that the engine be reset and re-timed, in addition to a new belt.

2. Bad fuel. Because of regulation requirements now in effect nearly the world over, bad "batches" of fuels are nearly non-existent. The fuels would have to sit unused and neglected for years before becoming so fowled that they would cause any serious damage to an engine/fuel system. But then, if you were to put those kinds of fuels in your vehicle, you deserve the results.


RE: What a deal!
By AnnihilatorX on 7/25/2012 5:13:56 AM , Rating: 2
Did you even read the article, the 40 mile range is the non-ideal one under desert heat. The ideal range is 100 miles


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