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Tesla Semi and Roadster could be relying on a “battery breakthrough”

Published

8 years ago

December 9, 2017

Evannex

Elon Musk and Tesla have made some bold claims for the new Tesla Semi and Roadster. Those who understand batteries have been scratching their heads trying to figure out how the company can deliver the specs it’s promising – and concluding that the only possible way is some as-yet-unannounced advancement in battery technology.

Musk says the Tesla Semi will be able to haul 80,000 pounds for 500 miles, and recharge to 400 miles in 30 minutes, which would revolutionize the trucking industry. As for the Roadster, its promised 0-60 acceleration of 1.9 seconds effectively shuts down every one of the world’s baddest supercars, and its touted 620-mile range would be double that of any EV produced to date.

However, industry experts are questioning Tesla CEO Elon Musk’s touted range and charging capabilities, saying the specifications defy current physics and battery economics.

According to Bloomberg, analysts at Bloomberg New Energy Finance point out that Tesla Semi’s announced specs would require a battery capacity of between 600 and 1,000 kilowatt hours (6-10 times the size of the largest Model S battery). Using current technology, an 800 kWh battery pack would weigh over 10,000 pounds and cost more than $100,000. That’s just for the battery – Tesla has said its entire truck will start at $150,000. It seems plain that Tesla is counting on falling battery prices to square the circle. “The first Tesla Semis won’t hit the road until late 2019,” Bloomberg points out. “Even then, production would probably start slowly. Most fleet operators will want to test the trucks before considering going all-in. By the time Tesla gets large orders, batteries should cost considerably less.”

It isn’t just the capacity of the battery that’s causing analysts to wear out their calculators – Musk’s claim that the Tesla Semi will be able to add 400 miles of charge in 30 minutes would require a charging system 10 times more powerful than Tesla’s current Supercharger – which is already by far the most powerful in the industry.

Tesla Semi Megacharger port could support 1 MW of power.

“I don’t understand how that works,” said Bloomberg New Energy Finance EV Analyst Salim Morsy. “I really don’t.” Tesla’s current generation of Superchargers have a power output of 120 kilowatts and can add about 180 miles of range to a Model S battery in 30 minutes. To meet Tesla’s charging claim for the Semi would require the promised Megacharger to deliver an output of at least 1,200 kW.

Perhaps Tesla’s biggest bombshell is the promise that it will guarantee truckers electricity rates of 7 cents per kilowatt hour, which Bloomberg estimates could translate to fuel savings of up to $30,000 a year. Musk says that adding solar panels and battery packs at the charging stations will account for at least part of the cost reduction. However, BNEF’s Salim Morsy insists that Tesla will have to heavily subsidize those electricity rates – he estimates that Tesla will pay a minimum of 40 cents per kWh. “There’s no way you can reconcile 7 cents a kilowatt hour with anything on the grid that puts a megawatt hour of energy into a battery,” Morsy said. “That simply does not exist.”

Of course, that’s no different from what Tesla does for its current Supercharger network, offering free electricity to many customers, while paying almost $1 per kWh to produce it, according to Morsy’s estimate.

And how about that Roadster? To deliver its promised range of 620 miles, it will need a 200 kWh battery pack, twice the size of Tesla’s largest currently available pack. Mr. Morsy predicts that Tesla will stack two battery packs, one on top of the other, beneath the Roadster’s floor.

Even with a double-decker pack however, it’s hard to escape the conclusion that Tesla is counting on improving battery tech to make the Roadster, like the Semi, feasible. Battery density has been improving at a rate of about 7.5 percent a year, and that’s without any major breakthrough in battery chemistry.

“The trend in battery density is, I think, central to any claim Tesla made about both the Roadster and the Semi,” Morsy said. “That’s totally fair. The assumptions on a pack in 2020 shouldn’t be the same ones you use today.”

A massive battery pack not only enables greater range – it’s also a key element in the Roadster’s world-beating 0-60 acceleration. Jalopnik’s David Tracy spoke with battery expert Venkat Viswanathan, a Mechanical Engineering Assistant Professor at Carnegie Mellon, who says that the 1.9-second figure actually seems reasonable.

Viswanathan explains that the power output of a motor is limited by the power draw from each battery cell. Because the Roadster’s pack is double the size, the power draw may not be that much more than that of a Ludicrous Model S.

Viswanathan told Jalopnik that the most modern battery cells offer specific energy of about 240 watt-hours per kilogram. Using that assumption, the Roadster’s 200 kWh battery pack should weigh roughly 1,800 pounds, a huge advance over the previous-generation Roadster. With clever use of lightweight materials, the Roadster could still come out under the nearly two-ton curb weight of the Nissan GT-R, an acceleration benchmark among sports cars.

Viswanathan concludes that a 0-60 time of 1.9 seconds and a range of 620 miles are quite feasible, although there are several other factors that will come into play – much depends on the vehicle’s tires and aerodynamics.

Meanwhile, at least one analyst thinks Tesla’s latest revelations (or claims, or fantasies, depending on your point of view) have implications that go far beyond the Semi and the Roadster. Michael Kramer, a Fund Manager with Mott Capital Management, told Marketwatch that he suspects improved battery capacities and charging times could make their way into all future Tesla vehicles.

“I’d have to imagine that Tesla has figured out how to put this technology on all of their cars, which means every car could get a full charge in under 30 minutes,” Kramer wrote. Once the Model S “is equipped with the 200 kWh battery pack in the new Roadster, which I can’t imagine is too far down the road, the range issue for the Tesla is officially dead.” (Elon Musk has said that Models S and X will not get physically larger packs, but improved energy density could increase capacity while keeping the size of the pack the same.) Someday soon, Kramer says, “The Model S would likely be able to drive further on one charge than a car on a full tank of gasoline.”

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Note: Article originally published on evannex.com, by Charles Morris

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EVANNEX carries aftermarket accessories, parts, and gear for Tesla owners. Its blog is updated daily with Tesla news.

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News

Tesla to make app change for easier communication following Service

“Looking into it. After a service visit is complete, we close the in-app messaging option after 2 hours. We will change this to 24hours or more.”

Published

16 hours ago

August 30, 2025

Joey Klender

Credit: Tesla

Tesla will enhance the ability to communicate through the mobile app with Service after work has been done on your car.

One of the biggest weaknesses of Tesla’s automotive division has been Service, as Service Centers are not necessarily plentiful, and wait times, in some regions of the country, are over a month in duration.

Getting in touch with Service after a car has work done to it is also difficult. Calling showrooms in some regions has proven to be difficult to enable direct communication between the customer and the company.

If something is not resolved properly, Tesla keeps the in-app messaging option active for two hours after the service visit is complete.

However, that doesn’t resolve everything, as some issues may arise again more than two hours later. Then the issue of communication presents itself once again.

Tesla is going to extend that time frame to a day or more, according to Raj Jegannathan, Tesla’s AI/IT-Infra, Cybersecurity, IT Apps & Vehicle Service VP.

Looking into it. After a service visit is complete, we close the in-app messaging option after 2 hours. We will change this to 24hours or more.
— Raj Jegannathan (@r_jegaa) August 18, 2025

Tesla has made several changes over the past few years to attempt to improve its Service. Recently, for Collision repair, it started offering a $45-per-day loaner program with free FSD, free tolls, and free Supercharging.

It also recently started sharing local and regional leader contact information so customers have the ability to reach out when they have complaints or disagree with warranty claims, changes in estimates, or initial diagnostics.

Tesla creates clever solution to simplify and improve its Service

However, this is only available at a few showrooms and is currently a pilot program.

These improvements are aimed at resolving communication breakdown, which appears to be a problem that many owners experience.

Tesla is one of the few companies that also operates a fleet of Mobile Repair vehicles, which will perform service at your house or place of business. However, the size of it has gone down by 11 percent year over year.

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Tesla is overhauling its Full Self-Driving subscription for easier access

The subscription model is more accessible to many owners, as it is reasonably priced and offers the option to take a month off from using it if they are interested in saving money.

Published

1 day ago

August 30, 2025

Joey Klender

Credit: Tesla

Tesla is overhauling its Full Self-Driving subscription and how it markets it to customers after several owners and fans of the company complained about the accessibility of the monthly access to its driver assistance suite.

Tesla Full Self-Driving is the automaker’s semi-autonomous driving suite, which is widely regarded as the most robust and capable on the market today. Owners can purchase the suite outright for $8,000, or they can subscribe to the program for $99 per month, an option it enabled a few years ago.

However, it is not super easy to subscribe to the subscription model, nor is it even recognized on the company’s Online Design Studio. Without some research or prior knowledge, a consumer might not even know they could pay monthly to experience Full Self-Driving.

That is set to change, according to Tesla’s AI/IT Infrastructure, Cybersecurity, IT Apps, and Vehicle Service head Raj Jegannathan, who said the company is planning to change that.

Instead of having customers only have the option to pay outright for the suite, Tesla is now planning to offer the subscription model in its Online Design Studio, making it easier to activate that option:

Yes, will optimize the design to offer both full purchase, subscriptions(with free trial) on the configurator.
— Raj Jegannathan (@r_jegaa) August 24, 2025

It will be the second major change Tesla makes to how it sells Full Self-Driving to customers, the first being videos of real-life operation of FSD in the Design Studio. Previously, the site only showed animations of Full Self-Driving’s capabilities.

Tesla added the videos of FSD handling some tricky situations, as well as general operation of the suite, to the Design Studio in recent weeks.

Tesla makes big change to encourage Full Self-Driving purchases

The subscription model is more accessible to many owners, as it is reasonably priced and offers the option to take a month off from using it if they are interested in saving money.

Many cannot justify paying for the suite outright, especially as it adds $8,000 to the cost of their car. After they experience its capabilities for themselves, they might.

Both moves appear to be an effort to increase the take rate of Full Self-Driving, particularly as autonomy takes center stage at Tesla.

With the rollout of Robotaxi and some teased capabilities of the upcoming v14 iteration of Full Self-Driving, Tesla is gearing up to continue advancing its self-driving technology.

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Tesla talks Semi ramp, Optimus, Robotaxi rollout, FSD with Wall Street firm

Published

2 days ago

August 29, 2025

Joey Klender

Credit: Tesla

Tesla (NASDAQ: TSLA) recently talked about a variety of topics with Wall Street firm Piper Sandler, as the firm released a new note on Friday about their meeting with the company’s Investor Relations team.

According to the note from Piper Sandler, Tesla talked in detail about the Semi program, Optimus, and its potential valuation given its capabilities, the rollout of Robotaxi in Austin, and Full Self-Driving progress in the United States.

Tesla Semi Ramp

The Tesla Semi is set to enter mass production in 2026 at a dedicated factory near the company’s Gigafactory in Reno, Nevada.

The Semi has already been in pilot program testing, as Tesla has partnered with a few companies, like Frito-Lay and PepsiCo., to perform regional logistics. It has been met with excellent reviews from drivers, and it has helped give Tesla a good idea of what to expect when it makes its way to more companies in the coming years.

Piper Sandler said that it is evident Tesla is preparing for a “major ramp,” but it is keeping its expectations low:

“We’ve never expected much from this product, but we’d love to be proven wrong (Tesla is clearly prepping for a major ramp).”

Tesla Optimus and its value internally and externally

Optimus has been working in Tesla factories for some time, but its expectations as a product offering outside of the company internally have major implications.

Its role within Tesla factories, for now, is relatively low, but Optimus is still doing things to assist. By this time next year, Piper Sandler said Optimus should have bigger responsibilities:

“By this time in 2026, Optimus should be moving/staging parts within Tesla’s facilities.”

Outside of Tesla, Optimus could be a major beneficiary for companies as it could be a more affordable way to handle tedious tasks and manual labor. The firm believes that if Optimus can work 18-hour shifts, a cost of $100,000 per unit “would be justified.”

Tesla Robotaxi Expansion

The big focus of the firm with Robotaxi was Tesla’s expansion of the geofence in Austin this week. It was substantial, bringing the Robotaxi’s total service area to around 170 square miles, up from the roughly 90 square miles that rival Waymo is offering in the city.

Tesla Robotaxi geofence expansion enters Plaid Mode and includes a surprise

Tesla has doubled its geofence three times since its launch in late June, and it also revealed that its fleet of vehicles has expanded by 50 percent. It did not give a solid number of how many vehicles are operating in the fleet.

Tesla Full Self-Driving v14 launch

Tesla’s Full Self-Driving suite is set to have a fresh version, v14, rolled out in either September or October, and there are some pretty high expectations for it.

CEO Elon Musk said:

“The FSD release in about 6 weeks will be a dramatic gain with a 10X higher parameter count and many other improvements. It’s going through training & testing now. Once we confirm real-world safety of FSD 14, which we think will be amazing, the car will nag you much less.”

There is also some expectation that v14 could be the public release of what Tesla is running in Austin for Robotaxi. The firm confirmed this in their note by stating it “should enable Tesla owners to use software that is on par with Robotaxis in Austin.”

The only real hold up would be regulator skepticism, but Tesla can alleviate this with strong data.

The firm maintained its ‘Overweight’ rating and the $400 price target it holds on the stock.