Chevy Bolt - 200 mile range for $30k base price (after incentive)

[Jeff N]

Electric motors being perfectly balanced beat the ICE at that type of vibration but can introduce rotational vibrations that vary with torque. In my '14 Spark I only hear the tread noise and tire drumming which completely mask any motor sounds. My MS has a noisy motor unit and the Roadster does not, but they both have the same high 'final ratio' feel to them as you go up and down the speed range. The '14 Spark on the other hand feels like driving a big car with a big engine that is stuck in 3rd gear (and 4th gear once you get going). There's nothing else like it, although the Fisker might be similar what with that big heavy-equipment drive unit.
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Some of this might be due to the Spark EV using a planetary gear set to implement the final gear reduction. Tesla, the LEAF, the Bolt EV etc. do not do that.

Planetary gears can be quieter because there are more gears in simulanteous contact sharing the torque load. A downside of planetary gears is that they have higher internal friction for the same reason and so are somewhat less efficient. The Bolt EV is a larger and heavier car but has nearly identical efficiency for that among many other reasons.

 

[wycolo]

> the Spark EV using a planetary gear set [Jeff N]

There is just something pluperfect about planetary gear sets, as a concept anyway. The Sturmey-Archer three speed British bicycle hub that never failed and provided a magical solution to human self propulsion was a milestone that used planetary gears.

The ability of GM to jump to a clean-sheet creation whenever it might prove useful always amazes me. Looks like they tried a whole bunch of different approaches ( the EV-1, the hybrids, Volts & Sparks) before settleing on the Bolt.
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[SageBrush]

There is just something pluperfect about planetary gear sets, as a concept anyway. The Sturmey-Archer three speed British bicycle hub that never failed and provided a magical solution to human self propulsion was a milestone that used planetary gears.

Interesting!

I didn't know anything about planetary gear sets until I bought my first Prius, and have been an admirer ever since.

 

[Saghost]

Interesting!

I didn't know anything about planetary gear sets until I bought my first Prius, and have been an admirer ever since.

They're a staple of the automatic transmission and bicycle hubs - and perhaps the most demanding application, helicopter gearboxes, where they have to convert 17,000 rpm gas turbines into 200 or 300 rpm rotors in a high vibration environment and the lightest box possible.

 

[SageBrush]

They're a staple of the automatic transmission and bicycle hubs - and perhaps the most demanding application, helicopter gearboxes, where they have to convert 17,000 rpm gas turbines into 200 or 300 rpm rotors in a high vibration environment and the lightest box possible.

I gather that they are also used in axle differentials.

 

[Saghost]

I gather that they are also used in axle differentials.

It's possible to do, but not traditional. Most differentials use a caged set of bevel gears, and a big bevel ring gear.

 

[McRat]

I gather that they are also used in axle differentials.

The classic spider gear differential is not a classic planetary design, but is functions on the same principle. It has an infinitely variable axle ratio because the spider gears inside the carrier is free to spin. The ring gear and pinion establish the base ratio, but the rotation of the spider gears inside the carrier divide the RPM differently to each axle. The Torsen is different though.

 

[wws]

The Model T had planetary gears over 100 years ago. And as previously mentioned, the classic Sturmey Archer 3-speed bicycle hub and its successors have also been based on planetary gears - also for over 100 years.

 

[schonelucht]

Opel is starting to show the Ampera - e to the European press. Reviews are a bit mixed. There is some disappointment that fit and finish are not up to Opel standards (which are relatively high for their usual segment). Base price before incentives and sales tax in Belgium is guided to be around 33 000EUR. In Germany after incentives and including sales tax of 19% the price is 34 990 EUR. First availability in Norway, then Germany, Denmark and the Netherlands late June.

 

[AndY1]

 

[wycolo]

Sales of the BOLT, being what they may, do appear to have had a positive effect on the Spark-EV market as evidenced by a 2014 LT2 (with fast charging option) going for under $9k on Craigslist. Seller claims a full recharge in 30 minutes. For such usability and small $$ one's rigid range requirements might quickly disappear into the Reality of simply charging on a daily basis and searching out fast DC stations that might be pressed into service when needed. Without the DC option you can now get these for under $7k, which has got to be the best ever bang-for-the-buck in the EV world.

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[Oil4AsphaultOnly]

Sales of the BOLT, being what they may, do appear to have had a positive effect on the Spark-EV market as evidenced by a 2014 LT2 (with fast charging option) going for under $9k on Craigslist. Seller claims a full recharge in 30 minutes. For such usability and small $$ one's rigid range requirements might quickly disappear into the Reality of simply charging on a daily basis and searching out fast DC stations that might be pressed into service when needed. Without the DC option you can now get these for under $7k, which has got to be the best ever bang-for-the-buck in the EV world.View attachment 225026

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That's great and all, but used Leaf's with Chademo have been at that price (and lower) for awhile now. New 2014 leaf had longer range than sparkEV's. How have their battery life fared? Are the used sparkEV's holding up batter on range?

 

[Saghost]

That's great and all, but used Leaf's with Chademo have been at that price (and lower) for awhile now. New 2014 leaf had longer range than sparkEV's. How have their battery life fared? Are the used sparkEV's holding up batter on range?

I haven't read much on the subject, one way or the other. Do note that the Spark EV has a solid TMS, unlike the Leaf and Energi twins which have the big degradation problems.

 

[brucet999]

I haven't read much on the subject, one way or the other. Do note that the Spark EV has a solid TMS, unlike the Leaf and Energi twins which have the big degradation problems.

OK, I'll bite. What is TMS? I'm pretty sure it is not the first definition Google came up with - transcranial magnetic stimulation - although, depending on position of the battery…

 

[jas]

I think its Thermal Management System.

 

[Saghost]

OK, I'll bite. What is TMS? I'm pretty sure it is not the first definition Google came up with - transcranial magnetic stimulation - although, depending on position of the battery…

Right, a Thermal Management System.

The ability to heat and cool the battery pack, including holding it below ambient temperatures when required. The key thing that sets the GM and Tesla EVs apart from a lot of the others.

Anyone who is serious about making EVs uses a liquid heating/cooling system - most of the rest use air or nothing at all. (BMW has a weird system on the i3 that allegedly uses the A/C refrigerant directly to cool the cells?) Ford put a real TMS on the focus electric, but not on the Energi twins. VW put a liquid TMS on the A3 Etron and Golf GTE PHEVs, but apparently not on the e-golf?

Cars without the ability to manage battery temperature often show pretty poor degradation; those with a good TMS generally hold up very well.

 

[brucet999]

Right, a Thermal Management System.

The ability to heat and cool the battery pack, including holding it below ambient temperatures when required. The key thing that sets the GM and Tesla EVs apart from a lot of the others.

Anyone who is serious about making EVs uses a liquid heating/cooling system - most of the rest use air or nothing at all. (BMW has a weird system on the i3 that allegedly uses the A/C refrigerant directly to cool the cells?) Ford put a real TMS on the focus electric, but not on the Energi twins. VW put a liquid TMS on the A3 Etron and Golf GTE PHEVs, but apparently not on the e-golf?

Cars without the ability to manage battery temperature often show pretty poor degradation; those with a good TMS generally hold up very well.

Is the Tesla cooling fluid chilled or simply run through a heat exchanger up front?

 

[MP3Mike]

Is the Tesla cooling fluid chilled or simply run through a heat exchanger up front?

It depends on how much cooling is needed. It starts with passive cooling, just running it through a radiator in front, with a fan, but if it needs to cool it quicker it can switch to active cooling mode where they direct the flow through a chiller.

 

[Saghost]

Is the Tesla cooling fluid chilled or simply run through a heat exchanger up front?

Tesla has the ability to chill when needed using a second evaporator in the cabin AC system - exactly the same approach GM uses, actually.

For normal operation in decent weather, it just uses a radiator up front.

 

[EVNow]

You can look at Leaf and Volt ramp up too. They were car assembly constrained too, not pack constrained. I haven't seen an example where the launch ends up pack constrained.

Leaf '13 was pack constrained. Infact Nissan took a long time to bring the battery production to US. So was the 30 kWh Leaf, early on.