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NorthernPiker
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Vibration and noise apparently are issues with switched reluctance motors, although some noise may be desirable for EVs to alert pedestrians, cyclists and other vehicles. These issues are being addressed (search "noise level for switched reluctance motors").
In extreme weather conditions, solar power with battery backup could be more reliable than the grid, particularly if a fully charged EV was in the driveway. Furthermore, If the weather event is localized the EV may be able to recharge repeatedly at remote sites that still have power. For widespread events, such as occurred in the Florida Keys, an EV would only represent a possible one-shot source of battery power.
For a given energy storage, this new chemistry also uses almost 50% less lithium and 75% less cobalt. (The cost of phosphorous is in the noise.)
The real world capacity of a nominal 41 kWh battery is more like 30 kWh since the battery pack would have a very short cycle life if it was cycled from 0 to 100% state of charge. So, these optimistic range numbers (e.g. 400 km) border on the ridiculous, which unfortunately taints a range that is probably closer to 250 km, which would be quite acceptable for the vast majority of users.
Brian P., you nailed it. I can only add that once 200 mile range EVs become available from multiple manufacturers at a price that is competitive with equivalent-sized ICEs, EV manufacturers will be very busy ramping up production, and oil companies will be dealing with continuously eroding product pricing, with the temporary side effect of keeping used gas hogs on the road. Nevertheless, the volume manufacturing of batteries and technical advances will enable cost competitive EVs with 300 mile range and above for those who truly need it.
This article is quite realistic, i.e. pessimistic w.r.t. FCEVs – 70,000 annual production by 2027, cost of green hydrogen, expensive refueling stations …. It does identify the strengths of FCEVs vis-a-vis BEVs, “refueling times and range”, but immediately notes that “battery technology is catching up”. What is also worth noting is that BEVs, as well as FCEVs, albeit limited by their likely low market share, would also be able to provide back-up grid power in the case of extended outages. However, BEVs can also smooth out grid demand as well as collectively providing grid voltage regulation.
The annual US electricity consumption is about 3,900 TWh. Conversion of all US transportation to electrical power would increase US consumption by less than 1,700 TWh, 59% of which would be for light duty vehicles (cars, pick-ups, van and SUVs) and 22% for medium/heavy trucks, or less than 1,000 and 400 TWh, respectively. Once this conversion begins, EV charging stations, both public and private, will increase in number and features - charge rate, contact/magnetic coupling, portable (road-side assistance), hours, etc.
The rate of discharge of 0.27A g-1 for a battery with a capacity of 0.620 Ah g-1 implies a C/2.3 discharge rate. For a 60 mph average speed, this rate is faster than an EV with a 200 mile range (C/3.3) or a 500 mile range (C/8.3). So, 0.27A g-1 is a conservative cycle test value for use in EVs with a 200 to 500 mile range. At 0.028% capacity loss per cycle (99.972% capacity retention per cycle), the battery would be down to 90 %, 85% and 80% of initial capacity after 376, 580 and 797 cycles, respectively. Using 80% capacity as the end of life for battery packs, the drop in capacity is linear enough to use 90% of initial capacity as the average capacity over the battery’s life. Then, on their original battery packs, a 200 mile EV would travel over 140,000 (= 180 x 797) miles on its initial battery pack and a 500 mile EV, almost 360,000 miles. A promising chemistry; now for manufacturability, calendar life and other realities ….
The battery cost for the GM Bolt is $145 per kWh, as per an Oct. 1, 2015 GM presentation, according to this link, which also quotes a source (John McElroy) that states that it ($145) is “$100 cheaper than what anyone else is paying.” http://insideevs.com/lg-chem-ticked-gm-disclosing-145kwh-battery-cell-pricing-video/ So much for a cost of “$350 per kW last year ”. It looks like EVs will reach 35% penetration of the LDV market well before 2040.
@HarveyD; it's 120 horsepower per US gallon. 120 horsepower = 89.5 kW and 1 US gal. = 3.78 liters; therefore power density = 23.7 hp/l, which is 5.3% less than 25 hp/l )but close enough after power losses?)
A $78 yearly saving at these low gas prices is good, unless, these tires would be much more expensive that the comparative tires. Higher efficiency would suggest a quieter tire, but what about other attributes like gripping capability.
mahongj, the corner case becomes a much smaller issue for a off-grid homeowner who owns a medium/high-range BEV near a public charging station. Then again, autonomous vehicles may enable "car as a service" and less car ownership....
At 15.27 million gallons per year per square kilometer, or 15.27 gallons per sq. meter, and 22.2 kWh/gallon, the annual energy output is 339 kWh/sq. meter. This implies an efficiency greater of about 20%, given a solar isolation of 1500 to 2000 kWh per square meter, not 12%. So, there must be another unquantified loss in the process.
Both the present cost (~ $490 per kWh) and the 2024 cost (~ $330 per kWh) of automotive Li-ion batteries, as well as the less than 4.4% annual decrease in cost seem quite pessimistic - perhaps a source of short-term comfort to ICE bigots but ultimately a disservice to clients. Respective costs of $300 and $150 per kWh and an 8% annual decrease in cost would be more in line with current consensus and indicative of a possible EV tsunami circa 2025 - 2030, for which automotive companies must be prepared.
Harvey, a 3-3-3 battery would enable a no-compromise EV with a life cycle cost less than an equivalent ICE. A 5-5-5 battery would ultimately limit ICE's to niche applications.
This study is flawed in that the upper limit of light-duty vehicle (LDV) penetration in 2050 is too low – “40% of vehicle miles travelled”. The study should have also examined cases of up to 90+% penetration. Even at a glacial 8% annual improvement in battery technology, batteries in 2050 would have improved by a factor of 10, in which case, few people would purchase an ICE LDV (car, van, SUV or pick-up)at a higher price and with fuel and maintenance costs that are 3 to 4 times that of an equivalent EV. Furthermore, in the unlikely event that EVs do not displace ICEs in the LDV category, FCEVs probably will.
Would a more efficient tire also be quieter than a normal tire? Just like a more aerodynamic car should be quieter. In combination with electric motors, this should be good news for people who live near busy streets and highways; not such good news for hearing-impaired or distracted pedestrians. :-)
Henry, in the pathological case of all of the electricity coming from coal, then an EV will produce about 10% more CO2 per mile than an equivalent gas-powered ICE. On average, a grid-powered EV will produce half the CO2 as its ICE equivalent and grid generated CO2 will go, whether through elimination of fossil fuels or the by the use of the so far mythological carbon capture. Any cost advantage of hydraulic hybrids over electric hybrids should disappear as battery technology improves and battery production soars for BEVs and PHEVs, which each use an order of magnitude more batteries than an HEV.
Similar energy and cycle life results are claimed by Nankai University in a 03 Jan 2015 GCC article, but using sulfur nanodots. Some cycle life claims are 895 mAh/g (~ 1.3kWh/kg) for 300 cycles @ C/2 and 528 mAh (~ 0.75 kWh/kg) for 1400 cycles @ 5C. So, supposedly the cycle life at C/5 rate, which is appropriate for a BEV with a 300 mile range, would seemingly be in the 1500 cycle range (~ 1 kWh/kg). However, factors eroding this implicit 450,000 mile battery life would include: 6-minute (C/10) charging episodes, calendar life (450,000 miles/ 12,000 miles/year = 30+ years), rapid acceleration/braking and ambient temperature, as well as the other non-cathode battery components.
Repair Shops will also lose business as minor scrapes should be repairable with fine grit paper.
Does it use inorganic or organic fluid? "The system uses water-based solutions of inorganic chemicals ..." "In the proposed system, energy is extracted by partial oxidation of an energy-dense organic liquid fuel ..." Nevertheless, the flow battery approach would allow energy storage (amount of inorganic/organic fluids) and power capabilities (size of bipolar cell stack) to be optimized separately. Early in the game, but it's certainly interesting.
Link to report http://www.nature.com/srep/2013/130605/srep01810/pdf/srep01810.pdf
@KitP; I was referring to the CMU life cycle analysis only for the energy, ~ 470 kWh per kWh, required to manufacture a Li-ion battery and the source of this energy. Yes, the LCA for GHGs is also quite good and it could bring some sanity to GHG discussions.
In terms of electrical energy required per nominal kWh of battery storage, the ESOI of li-ion batteries would be about 40 for the life time electrical energy out to electrical energy in. The life time electrical energy out to the total energy in is about 12 as the article states but only if all the energy comes from fuel - 75% to generate electricity and 25% for fuel for mining operations. This distinction should have been made in the article. http://pubs.acs.org/doi/suppl/10.1021/es702178s/suppl_file/es702178s-file004.pdf I would be more interested in an article on how much energy storage, electrical, thermal, etc., will we need.