Stark Battery Tech Thread

[Theo]

I don't see fast charging as much of a technical hurdle as reaching energy density in the 500s Wh/kg?

After all, commercial 21700 cells like Molicel P50B released in 2024 was already rated 5C allowing 15ish min charging.

Of course it would degrade cycle life but we're really close from that not being a concern anymore: P50B is rated at 750 (5C/-1C) cycles for 80% retention, CATL just unveiled a 5C cell rated for 3000 cycles at 80% retention (not many details not any release date yet).

In this coffee break charging goal, I believe the real hurdle is charging infrastructure. And here the limitation comes from your government rather than the technology.

I think that one of the main technical problems is heat. Let's say that a fast rider uses the whole charge of a 6.5 or 7.2 kWh battery in 0.5 hours, that means that the average power output has been roughly 14 kW. On the straightaways he probably used way more but then there is also braking and cornering.
Now, such a rider could potentially overheat the bike, especially if the environmental temperature is high.
Then this rider puts the bike under charge and now the charging power is maybe 7 kW or more, but it's continuous. The chances of overheating keep being high.
IMO it would be cool, no pun intended, if they managed to make some kind of tool that can significantly actively cool the battery and if necessary the powertrain while fast charging. Maybe something with peltier modules, for example.

 

[happyinmotion]

Cars have fully shifted to water-cooled batteries so they can have fast charging without overheating. I think that's going to be valuable for bikes, despite the smaller size of batteries. Liquiud battery cooling won't work for the Varg platform but I'm assuming the next bikes will be different.

In this coffee break charging goal, I believe the real hurdle is charging infrastructure. And here the limitation comes from your government rather than the technology.

Absolutely. NZ government decided to just let the free market handle it and that's a foolish way to do infrastructure. Of course now we have ten different networks needing ten different apps and ten different accounts for a country that's got a population the same size as Alabama. And somehow fast charging ended up as much as buying petrol.

 

[Beagle]

Can't find any online trace of Stark livestream about battery tech that was supposed to happen yesterday?

We don't really need Anton taking down Donut to know it's pure BS: there are conflicting news from Verge and Donut but Verge motorcycles deliveries could have suddenly been delayed from March 26 to end of the year 26 for Estonia/Finland and well into 27 for other countries. It could be dates for just "orders made today" but they have made contradictory statements regarding this.
By their own admission, annual production capacity is supposed to be 350 motorcycles. Which would still be huge for them since they've only ever made about 100 motorcycles since the company started in 2018.
And the bike is not certified anywhere at the moment...
Don't hold your breath folks.

https://insideevs.com/news/786388/verge-motorcycles-donut-labs-solid-state-battery-ev/

 

[Proxxon]

Can't find any online trace of Stark livestream about battery tech that was supposed to happen yesterday?

Noticed they went live on their instagram page, but was to late to join it live. And now I can't see it anywhere.

 

[Beagle]

I wasn't sure where to put this:

here's an interesting vid about battery swaps. To make a long story short, some regional league rider wanted to race what might the most famous sand race: Le Touquet enduro.

Race lasts 3 hours, he planned to swap batteries every 20 min, anyway safety commission said no so for this year he will have to make do with 45 min exhibition electric race.

The interesting bit is that they've filmed his partner training for sub-1 min battery swaps and the mechanic explains in some details the modifications made to the bike (especially chassis) for hot swaps, it starts at 18 min. They've also got a monstrous device to lift the front wheel. Training in the shop it took 3 people, 39 seconds!

 

[Swank171]

Unfortunately I think it's kinda like asking Honda if you can buy just the new engine to fit in your old frame instead of the whole new bike.

That does not fit with OEM business model.

Plus from an engineering point of view, you don't want any external constraint linked to retrofitting when you're designing a new bike, you want to take all the advantage you can to make the best possible bike. If you need to slightly alter the battery case dimensions to make it better fit with the new frame, you don't care that it won't fit in the old bike.

Sorry, don't put high hopes on this.

I think there is a difference……for one the motor updates don’t increase range and charging capability.

Also the cost of a motor isn’t 50% of a 13k bike…..a battery is far more expensive.

Pending updates to battery tech is a HUGE deterrent for consumers that know a lot will change in the next year.

 

[Swank171]

If anyone had to take an educated guess when do you think we will see another battery related range upgrade? Not software.

I sold my gen 1 feeling like there would be a new one soon and 2 weeks later 1.2 dropped.

Now I wanna buy a 1.2 but if we are up for another 20% increase in the next few months I wanna wait! Haha.

I’m sure everyone would love this answer but I thought it would be a good talking point in the battery tech thread.

Also for you super smart battery guys…how much improvement on range do you think is possible just in software updates increasing efficiency in current 1.2 FORM?

 

[Captblues]

Battery tech is like intel micro chips, every year there is a better one. Right now there are better batteries out there with higher density than the 1.2 model. So if I were to guess, and it is just a GUESS, late summer or fall 1.3 model.

 

[Beagle]

I'll guess new battery every couple of years?

This time I expect them to first release the ALG, then a few months later update the Varg range with the new cells. Could be proper Varg 2.0.

 

[Karinshi]

Battery tech is like intel micro chips, every year there is a better one. Right now there are better batteries out there with higher density than the 1.2 model. So if I were to guess, and it is just a GUES, late summer or fall 1.3 model.

late summer is too soon in my opinion for an updated Varg

I don't think the Varg 2.0 will arrive before May/June 2027.

First, they have to properly develop the ALG (they're still testing the new cells with A123). There's still a lot of testing to do. Then they have to present it and launch it on the market... which I don't think will be in 2026. It will probably be in the first quarter of 2027, December 2026 at the earliest, just like the EX. And I don't think they'll present the Varg 2.0 with a new battery until at least 6-8 months later. So far, they've managed to reach 9 kWh in recent tests, but I think they should really be aiming for 10 kWh; that's THE NUMBER.

I'm intrigued by how they're going to manage the new cell and its different dimensions within the Varg chassis... worthy of in-depth study

 

[Karinshi]

Consider that by creating a VARG 2.0, all 3 models would already be improvable, and the SM has only been on the market for three months, with the first deliveries just a month ago... it doesn't make sense to have an update already in the summer... especially since the SM is the model that most needs a battery upgrade.

It wouldn't be a bad idea to offer two battery options on the 2.0, as we've discussed before. Here's my realistic calculation:

Right now, it's almost 100% confirmed that a density of 330 Wh/kg is possible, but I think if they could achieve 360 Wh/kg, things would improve significantly, because they could manufacture:

Lightweight battery: 360 Wh/kg x 20 kg battery = 7.2 kWh (which is the same as now but 8 kg lighter)

Large battery: 360 Wh/kg x 28 kg battery = 10,080 kWh (with the same weight as now)

A DREAM

 

[Karinshi]

Just to compare, last night i went on a ride with my EX with SM wheels (15/47 sprockets) with 2 friends, one with husq 701 and the other with ktm 690smc r 2024... they have full tank, me at 100% battery, same driving... 50% fast driving 50% chill, 80km later i had 8% battery and they have 40% tank left... SM is not there yet, even with a 10kw battery i will be shorter on range, much better, but no the same

 

[Beagle]

Love your enthusiasm @Karinshi

Personally I'm more excited about the ALG, if they can hit 15 kWh while keeping weight under 150 kg that could be a great dual sport bike.

edit: of course needs CCS compatibility for the 10-15 min "coffee break" charge, that would be a game changer and much needed for road bikes.

330 Wh/kg is 45 kg for 15 kWh, so adding 18 kg in cells compared to Varg EX, it might be doable to double the range while keeping additional weight under 30 kg (so bike weight under 150 kg), just do it

Hardest thing may be to make it at a competitive price, it would probably be marketed as an expensive adventure bike rather than a modest dual sport bike.

 

[Karinshi]

Love your enthusiasm @Karinshi

Personally I'm more excited about the ALG, if they can hit 15 kWh while keeping weight under 150 kg that could be a great dual sport bike.

edit: of course needs CCS compatibility for the 10-15 min "coffee break" charge, that would be a game changer and much needed for road bikes.

330 Wh/kg is 45 kg for 15 kWh, so adding 18 kg in cells compared to Varg EX, it might be doable to double the range while keeping additional weight under 30 kg (so bike weight under 150 kg), just do it

Hardest thing may be to make it at a competitive price, it would probably be marketed as an expensive adventure bike rather than a modest dual sport bike.

Yes, that could be good... what power would you choose? 80hp aswell?

 

[Beagle]

Yes, that could be good... what power would you choose? 80hp aswell?

Well, 80 hp MX bike is for marketing and bragging rights but for an adventure bike that's the bare minimum.
And FWIW I think they should ditch this "20 more hp for 1k" gimmick.

Not that "adventure" riders need nor really use more power but they expect more from an adventure bike, even more so when the manufacturer claims more power than the competition.

See
10 k€ 84 hp 223 kg Suzuki Vstrom 800,
11 k€ 73 hp 208 kg Yamaha Ténéré 700,
11 k€ 92 hp 210 kg Honda Transalp 750,
11 k€ 95 hp 203 kg KTM Adventure 790,
12 k€ 115 hp 214 kg Triumph Tiger 800,
16 k€ 115 hp 199 kg Ducati Multistrada 890 V2

Stark can easily make the Älg a lighter bike (under 200 kg), match or exceed hp (new motor, minimum 100 hp) but it could be hard to price competitively. Anything over Multistrada 16 k€ would be a very hard sell.

They'll need a battery twice as large as the Varg's, impact on retail price could be somewhat softened by much higher sales expected for a road bike but still... of the 3 specs that's probably the biggest challenge.

Weight is not insurmountable, 700-900 cc twin (or triple) cylinder engine weights about 50-60 kg (Ténéré 52 kg, Multistrada 55 kg), plus 8-10 kg exhaust line and more...
Stark 80 hp motor weights 9 kg so there is "room" for a hefty battery pack while staying lighter than ICE equivalent. 50 kg battery pack is 13 kWh with current cells, 16 kWh with 330 Wh/kg prototype cells they're testing.

 

[Erwin P]

I think the 790 ADV is the wrong competition since it's the budget line with budget suspension etc. Look into the 890 ADV R.

IF they use the same cells in every bike they can drop the prices since mass matters more than anything else.

A lott depends if they want to go big dual sport or light ADV bike with this.

 

[Beagle]

I think the 790 ADV is the wrong competition since it's the budget line with budget suspension etc. Look into the 890 ADV R.

IF they use the same cells in every bike they can drop the prices since mass matters more than anything else.

A lott depends if they want to go big dual sport or light ADV bike with this.

Yeah KTM 890 is 16k€ 105 hp 200 kg, similar to Multistrada (or 16 k€ 108 hp Tiger 900), at the top of midsize adventure bikes (however crazy it sounds to call 900cc midsize).

Price wise Stark will probably aim to get closer to these than to 11k€ japanese bikes.

 

[Erwin P]

I think Stark will fall in lone most with KTM. They did with the MX and EX as well. Also it's the same crowd they are after. Performance driven futuristic powerhouses.

And timing couldn't be better. KTM has the 790/890 camshaft issue. Production is rumored to move to India while the 790 allready is Chinese etc etc.
Premium high end performance from Europe has a vacuüm...

 

[happyinmotion]

Who wants to pick up a 200 kg bike? I would rather they target the KTM 690:

13 k€ 80 hp 160 kg

That would be a go-anywhere bike that I would not worry about dropping. It could use the existing drivetrain, adding 20 kg of batteries and 10 kg of charger and adventure gubbins. That would give us near-double the range of the current models plus fast charging.

The biggest selling bike in NZ right now is the CF Moto 450MT. It's selling more than twice as many as the Ténéré. It's the kind of lightweight adventure bike that no-one else was selling (recent Fortnine review). It's so popular because weight matters. So I'm hoping Stark can do the same - come out with a technically compelling bike at a reasonable price and a lower weight than the incumbents.

 

[Erwin P]

That CFMoto is 175kg dry. Wich pretty much means 200kg wet. A Tenere is 208kg wet, not a significant weight difference on a ADV.
Somehow the media picked up on it being ultralight but it isn't. 200kg bikes are the best selling bikes in NZ then
I think weight isn't even so much the thing, but did you notice it's just over half the price of a Tenere? I think we've found its USP.

Sure they could do a 160kg KTM 690 rival. But at being so light it would not have that much extra range, be very bare bones and thus no long travel bike. Not to mention 160kg tall bikes suck at open roads with some sidewinds. Weight matters in both directions.

Not to say i think they shouldn't do it. Just that they shoudn't forget about the ''midweight'' ADV class.