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Tesla’s Battery Guru Describes A New Cell With Massive Lifetime




A recent paper on new battery chemistries published by a team including Jeff Dahn, the physics professor from Halifax who is often called Tesla’s battery guru. The claimed results suggest a cell with a lifetime of 6,000 cycles. This would translate in a large pack car to the “million-mile battery” which Elon Musk has predicted for Tesla.

Professor Dahn knows very well the difference between an interesting battery result in the lab and much more involved tests, and the further difference between the involved tests and a battery in high volume production with high quality and good prices. The latter has not been shown and is hard to predict. The paper forecasts such batteries are good for robotaxis. In addition, these batteries do well even when run on a 0-100% discharge cycle. Today’s batteries do best on a 20-80% discharge cycle, so you get 66% more range from the same pack if you can safely do 0-100%.

First of course, such a battery would be good for regular electric cars. While no car today has a million mile lifetime (Elon Musk has claimed Teslas do) more battery lifetime is always good. Even if the car falls apart after half a million miles, you could still move that pack into a second car. It also reduces the embedded energy in making the batteries and the cost of recycling them. I doubt any car interior is ready for a million miles, nor is the exterior ready in some climates. Frames and electric motors might very well last.

The important difference with the robotaxi is that its wear happens fast. Put into heavy use, it can be doing 200 miles/day or more — even more if it does a lot of highway travel. The average New York taxi is driven around 180 miles/day — average urban speeds during core driving hours are just 12 to 20 mph including stops — while the average private car does only 40.

At 200 miles/day, a car would rack up a million miles in just over 13 years. A taxi with a more normal 250,000 mile life (which is how long New York taxis last) is worn out in 4 to 5 years. If you can make the vehicle last that long, you seriously reduce the depreciation part of the robotaxi economics model and thus reduce the cost of a ride, since today depreciation is the largest cost factor in operating a car. Depreciation of the battery has been one of the largest costs of operating (and fast charging) an electric car. In fact, you can reduce depreciation so far that it becomes secondary to other costs like energy, risk, maintenance and logistics.

Robotaxis will do a lot of their work during the three weekday peaks, which are morning and evening rush hour, plus the lesser peak of lunch. You can either equip the car with enough battery for the whole day, or you can put less battery in and try to get some charging done during the day. That saves you some weight and some space, but since a larger pack lasts longer, it doesn’t save you much other money. Daytime charging can be a plus for cars that will do long highway travel, and of course night travel.

Today, night charging is the whole game. Vehicles are idle at night, and that’s when power is the cheapest. Even if you thought a 2pm recharge would let you have a smaller battery, you would not do it because electricity can cost 2x to 4x as much. Results from Tesla suggest that having the 75kwh battery only loses about 5% of efficiency from that extra weight over the 50kwh battery. You don’t save a lot.

If your choice is to put in a 200 mile battery into the taxi, and recharge only when power is cheapest, or put in a 100 mile battery (which costs half as much but lasts half as long) and charge mid-day when power is expensive, the math points to the 200 mile battery, except on the question of space.

Once private cars become robocars, they get the ability to scoot off to charging stations when not driving their owner. This actually lets the private car get away with less battery for city driving, because it can boost up mid-day while the owner works or shops — but not if the daytime price is 4x as high.

Surplus Solar in the Day

Today’s electricity prices will change. The hope is to install a lot of solar power. If we installed immense amounts of solar power (in the sunny lands) this could make noon power cheap, maybe even cheaper than at night. One of the big barriers to massive solar deployment is you need storage to go along with it — electric cars come with storage. Electric taxis that grab daytime power when it’s sunny but will accept not getting it when it’s cloudy are the dream customer for solar. The biggest problem is that they want to be out making money at lunch, which is the peak time for solar. From 3pm to 7pm they will all be at work as well, but this is also the period of maximum grid demand.

Charging cars is the perfect match for both solar and wind, if the cars have big enough batteries that they don’t have to be picky about when they get their power. Cars can start drawing and stop drawing power on a millisecond’s notice as renewables ramp up and down. It is not perfect though — a car needs to get its power sometime, and if it’s rainy or the winds are calm, some cars can be allowed to get low, but not all of them.

(Another perfect user of renewables is the pool pump. Pool owners need to pump a large volume of water every day but they don’t care what hour they do it. I pump mine at night when the power is cheap. We’re also seeing air conditioners that make ice when the power is cheap and cooling is easy, and use it to cool when the thermometers rise and the power price soars.)

When power in the day starts costing a similar price to power at night, another resource becomes important — charging stations, especially fast ones. It might be wasteful to have a charging spot only be in use at night, so with low cost daytime power, you can and should make use of it most of the day. On the other hand, if a charging station is really just a parking spot with a box on the ground, it can be utilized as parking during the day, and charging at night.

Very long range robotaxis are their own problem. If somebody expects to go 300 miles in one, it needs a bigger battery, perhaps bigger than you want to install. One solution, aside from fast charging which still takes time and is not good for battery life, is to have one taxi drive 200 miles, and transfer the rider to another taxi that does the rest of the way while the first one charges. But it still wants to charge in the day.

Grid storage

Batteries with improved lifetime also make sense for grid storage, which is what we need to make use of solar and wind. While most people in the battery world focus on total capacity in kWh per dollar, or energy density in kwh/kg, one of the most important statistics for a battery in both cars and grid storage is “lifetime kWh” per dollar. That is to say, how many kwh will you put in and out before the battery is no longer useful? It is this number which determines the cost per kWh of storage, and today it’s higher than we would like.

This even starts to make “vehicle to grid” systems practical. I have been skeptical of the v2g concept, because for private car owners and fleet operators, energy in their car batteries is precious. It represents range they paid for and plan to use, and putting it in and out eats up battery life. If the usable capacity increases, and the cost of putting it in and out decreases, it can make more sense to handle grid peaks with cars. Especially if the cars, being robots, and rush off to plug in when the grid has a sweet offer for the power inside them. Unfortunately, the time the grid needs power most — about 7pm on a hot day when all the solar panels shut off and all the loads are on — is the time when many cars are still driving or have their batteries at the lowest point of their day, at least today.


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Paris tests new bubble-shaped water taxi




bubble-shaped water taxi

Paris is testing out a new form of travel: an eco-friendly bubble-shaped taxi that zips along the water up and down the Seine River.

Organizers are holding test runs this week on one white, oval-shaped electric hydrofoil boat that resemble tiny space shuttles gliding past Paris monuments.

The boats can fit four passengers, and if they get approved, can be ordered on an app like land taxis, shared bikes or other forms of transport.

Its designers hope to run the so-called Seabubbles commercially in Paris and other cities starting next year.

Anders Bringdal, SeaBubbles CEO, told The Associated Press that “the most important for us is no noise, no waves, no pollution. And bring them into cities that are congested.”

Bringdal said the water taxi will “not only be fun” but also makes economic sense.

“If you compare a similar size boat with an engine, you are going to run 30, 40, 50 euros an hour in fuel cost when this one costs you 3 dollars or 3 euros,” he said.

Proponents see the vehicle as a new model for the fast-changing landscape of urban mobility.

Copyright 2019 The Associated Press. All rights reserved. This material may not be published, broadcast, rewritten or redistributed.


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Google Fi launches a more traditional unlimited plan




google fi

Google is announcing a new plan for its MVNO Fi cell service: Unlimited. Like the big four carriers in the US, Google apparently feels the need to use the word “Unlimited” next to its service, whether or not it means what you think it means.

For Google, it means that a single line costs $70 for everything, two are $60 apiece, three are $50 apiece, and you can have four to six at $45 per line. The caveats — and there are always caveats with unlimited plans — is that Google “may optimize” video streaming down to 480p and will also throttle data for any single user that goes over 22GB per month. (You can pay $10 per GB if you want un-throttled data over 22GB.)

Google is also tying its new Unlimited plan to Google One, another service that hasn’t taken off in the popular imagination. Google says that the Unlimited plan comes with a Google One membership, which would save you the $1.99 per month it costs for the 100GB cloud storage tier.

But though that sounds complicated, it’s conceptually easier (at least in the US) than Google Fi’s previous plan — which is still sticking around but is now called “Flex.” Under that plan, it is $20 for the phone line, $15 for each additional line, and $10/GB for any and all data used. For a lot of customers, it could end up being much cheaper than other plans — though heavy data users could sometimes run into higher costs. Still, Google capped data costs at $60 per month.

The Flex plan is actually a really great deal for certain customers, but it meant that their bill could have wild swings from month to month depending on data usage. Google wanted something conceptually easier for US customers, the ones who have been seeing every other carrier offer Unlimited plans.

Both the Unlimited and Flex plans will allow customers to order free “data-only” SIM cards that draw from the same data buckets with no additional monthly charge. Most other US carriers charge a monthly fee for adding such devices, which makes Google Fi one of the best choices for people who love using LTE-enabled version of gadgets.

Fi also is popular with international travelers, as it doesn’t charge any extra fees for data when roaming, though it does $0.20 per minute for calls. Fi also offers a free VPN to Android users, to protect them on sketchy Wi-Fi networks.

Add all that up and Google Fi is one of the better deals in wireless, with bonus features that are actually relevant to wireless service instead of corporate media TV tie-ins. That hasn’t been enough to get it widespread usage, but maybe the new, easier-to-understand unlimited plans will give Fi a boost.


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Voyage Auto raises $31 million to expand self-driving technology




voyage auto

Voyage Auto Inc, the self-driving-car start-up, has just completed $31 million in Series B fundraising, which brings its total capital raised to $52 million.

Founded in 2017 by MacCallister Higgins and Oliver Cameron, Voyage’s mission to “build technology that brings self-driving cars to those that need it most” has attracted financial partnerships with Chevron Technology Venture, Jaguar Land-Rover’s InMotion Ventures, and Khosla Ventures. Franklin Templeton Investments led the Series B round of fundraising.

“Since investing in the company’s Series A in 2018, it’s been fantastic to watch the business go from strength to strength. They’ve shown us that they have the capability to quickly make self-driving, autonomous taxis in residential communities a reality, sooner than anyone would have thought,” said Sebastian Peck, Managing Director of Jaguar Land-Rover’s InMotion Ventures.

The Palo Alto, California-based start-up known for its self-driving taxi services in retirement communities has expanded its presence to Florida, where the cars navigate complex communities and deliver passengers to their doors at a maximum of 25 mph. While retirement communities have provided a controlled baseline to deploy their services, Voyage does not plan to stop there.

Voyage will use the funds to grow its talent base, expand the fleet of G2 model (Chrysler Pacifica Hybrid minivan), prepare to introduce the G3 model, and further develop its technology towards commercialization. Also, with this additional support, Voyage cars will be able to increase its speed in neighborhoods with a progressively more complex network of streets.

Voyage engineers have made significant strides in the safe-critical middleware, prediction systems, as well as its high-definition map navigation.

Since 2018, Voyage’s talent base has grown 300 percent. Voyage hired former Uber and Tesla employee Drew Gray as its Chief Technology Officer. David Bacchet, the company’s new Director of Autonomy, brings experience from Apple SPG and Tesla. Voyage has begun hiring for engineering, operations and leadership positions to maximize its expertise base.

The robo-taxi industry is projected to be worth $2 trillion by 2030, based on a thorough New York City simulation conducted by UBS Evidence Lab.

“The current number of taxis operating in New York alone could be cut by two-thirds once cars are fully autonomous,” the report said.


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