One piece of the Tesla Cybertruck launch we didn’t see coming (nor did Tesla event planners or CEO apparently) was the Range Extender, which we are still learning more about now. But what we already know answers some questions like how Cybertruck owners expect to tow or travel long distances, especially in the cold, without charging as often.

But the 130-mile add-on battery also presents some opportunities that harken back to when Tesla demonstrated battery swap stations. And its interface to the Cybertruck even presents opportunities for other energy sources from solar to hydrogen to even petroleum generators.

Range Extender omitted during the presentation

It is hard to tell if Tesla and CEO Elon Musk were supposed to have mentioned the range extender during the admittedly haphazard and cringey presentation but it would seem like a really big deal. For one, it would get the Cybertruck acceptably close to Tesla’s originally promised 500-mile range.

Tesla’s website says the Range Extender brings the mid-level Cybertruck to “470+” miles of range. That’s an additional 130+ miles and, if the 123kWh battery pack takes the Cybertruck 340 miles (2.7 miles/kWh), the range extender would need to be an additional ~47kWh.

Range Extender or Federal Tax Credit Extender?

By making 1/3 of the 500-mile battery an external accessory, Tesla was able to keep the price just under $80,000. That allows it to qualify most owners for the $7500 tax credit which is a significant savings and could be put towards the rest of the 500-mile battery on Uncle Sam’s dime.

Also, being frank here, most owners will not need a 500-mile battery even if it makes them feel a lot safer. But the prospect of being able to add more range at a later time might allow some potential buyers to make the purchase and “see how it goes” with just 300 miles of range.

How much does the Cybertruck Range Extender weigh?

47kWh is a huge and heavy battery, one bigger than some medium-range BEV‘s batteries. We’re talking on the order of 1000 lbs. As an estimate, we can take the 454kg ~75kWh 4680 battery pack weight of the Model Y battery and figure that at about 2/3rds the size, the Range Extender will come in at 300kg or 660lbs. Or more likely around 700lbs, if you consider the interface, packing challenges, safety, ruggedness, and efficiencies of a smaller pack.

Remember, Tesla will have to build this 700lb high-density/inertia object to not come flying through the cabin in a front-facing collision. It will also affect the performance of the vehicle in the same way that putting 4 more people in the cab.

How much does the Tesla Cybertruck Range Extender Cost?

Since Tesla didn’t talk about it at the event and it doesn’t have a sticker price on the customer-facing website, we can’t be certain. However, in the website source code, the following was found:

$16,000 seems like a bit of a premium on what an external 47kWh battery would cost. Assuming Tesla has hit the $100/kWh on the 4680 cell level, that’s a cost of $4700 and another $11K for packaging, production, and a fat margin.

That price could change and hopefully come down as the scale increases and would probably be a lot more popular with towing Cybertruck owners at under $10K.

Bigger questions

So now that we can guess the size specs and price of the Cybertruck Range Extender, we can think about what it means for the vehicle.

At close to 700lbs, this isn’t something that 1 or 2 people can just install themselves. It is going to take either a hydraulic jack/forklift type of installation or a more permanent fixture that would be installed at the factory. It will also either need to have its own BMS and cooling system or tap into the Cybertruck’s heating/cooling liquids. So what I’m saying is that the interface might not just be a big DC plug.

Range Extender as a Powerwall?

In a perfect world, you could leave your Tesla Range Extender in your garage and it would act like a 3-pack of 14kWh Tesla Powerwalls, saving you from power outages and maybe earning some grid-shaving money from day to day.

Then when it was time to tow the boat up to the mountains or go on a cross-country vacation in the cold, you could “throw” it in your Cybertruck bed and use it as extra range and then as a Powerwall for the lake house.

Range Extender battery swap?

Tesla had a Model S battery swap station in California in 2015 that would allow a new battery to be installed quicker than a gas fill-up. It never went live because, in Tesla’s words, they saw that charging was getting so quick that it wouldn’t need the complexities of a battery swap soon. Additionally, not all batteries are the same, and older batteries aren’t worth nearly as much as new ones so people could be losing money on the value of their car on a swap.

The Chinese manufacturer Nio is the only current company offering a significant battery swap option for EVs.

However, if the Cybertruck becomes as popular as it initially seems, maybe it makes sense for Tesla to run some range extender battery swap stations. A quick stop with a forklift could add 130 miles of range in a few minutes. Maybe multiple batteries could be added at the same time? Put these at the base of ski mountains and the outskirts of deserts?

Or more realistically, instead of buying a Tesla Range Extender, rent one for that week’s vacation to the mountains for a fraction of the cost. These could be picked up and dropped off at Tesla stores or 3rd party outlets. Maybe a super high-power automated battery swap station like Gogoro. Maybe it is manned by super strong Tesla Optimus robots (lol).

More Range Extender options

If it is a bi-directional interface (and how else would you charge it?) it could also be used to DC fast charge other things…like the Cyberquad! Seriously though Cybertruck owners could DC fast charge electric ATVs, boats, and motorcycles a lot faster than the 9kW Level 2 power that the Nema 14-50 outlet would provide.

With Tesla’s range extender interface, one could also see the company offering different battery sizes. Maybe a 50-mile option that could be carried by a tow truck driver. Or a longer range 250-mile option? 500 miles?

Or solar? We know Tesla plans to put a solar tonneau cover into production so this could be the interface there. While this will be a microscopic amount of power at any given time, it will add thousands of miles of range over the life of the vehicle. Just don’t expect to drive on solar like a Solar Race car.

Even better, why limit it to battery packs? What if Tesla offered a 1000-mile hydrogen or *gasp* gasoline generator alternative for those way out in the sticks? Yes, I know very unlikely that it would get Elon Musk’s approval but maybe if Tesla opens the connector to 3rd parties, it wouldn’t be rocket science to deliver bespoke power options.

I can already imagine someone doing a cross-country Cannonball run with the Cybertruck where it doesn’t ever need to stop. On FSD? Elon hook us up.