cageymaru

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Tesla has entered into a definitive agreement to purchase Maxwell Technologies for $4.75 per share. Maxwell will become a Tesla subsidiary and will be wholly owned by Tesla. Maxwell is developer and manufacturer of Innovative, cost-effective energy and power delivery solutions. The company is known for its patented dry electrode technology used in its ultracapacitors, which can be used to manufacture batteries. Maxwell ultracapacitors can be recharged virtually instantly and are the perfect solution for regenerative systems which are found on electric cars. Batteries have a narrow operating range and perform poorly at low and high temperatures alike. The Maxwell ultracapacitors can operate all the way down to -40C. Maxwell ultracapacitors perform reliably through one million charge/discharge cycles. Typical batteries can only last through a few thousand charge/discharge cycles. Maxwell also makes power smoothing solutions for utility grids and signed a deal with Geely/Volvo to implement its designs into the automotive sector. The closing of the deal is subject to regulatory approvals and is expected to be completed by Q2 2019.

"We are very excited with today's announcement that Tesla has agreed to acquire Maxwell. Tesla is a well-respected and world-class innovator that shares a common goal of building a more sustainable future," said Dr. Franz Fink, President and Chief Executive Officer of Maxwell. "We believe this transaction is in the best interests of Maxwell stockholders and offers investors the opportunity to participate in Tesla's mission of accelerating the advent of sustainable transport and energy."
 
This:
upload_2019-2-4_12-9-12.png


Bought this?
upload_2019-2-4_12-9-33.png


Hmm... o_O
 
Seems like a worthy addition. I wonder if the goal is to be able to charge in same or less time than ICE take to gas up. I guess we'll find out.
 
Ultracaps/Supercaps have high discharge, great operating temp ranges, and charge endurance (their quantity of cycles), but very poor power density. It's like 10 seconds of power versus 1 hour for the same space occupied. Lithium based batteries on the other hand tend to have a curve that goes from low-current-out / high-density to high-current-out / low-density (depending formulation, design-spec).

So I wouldn't assume they're going to be dropping a bunch of caps in a Tesla as a battery. My guess is they wanted the dry electrode technology. There's other companies experimenting with dry electrodes in their Lithium batteries as it allows them higher energy density because they don't have to use balancing alloys (more lithium). The problem with using just lithium in the past was that it bridged really quickly, so other metals were mixed in to increase the life. A solid electrode prevents that.

They likely already use the caps in Tesla's for the initial motor inrush current to protect the batteries. When overcoming the inertia required to move, the motor can draw significantly more current for a short period (perfect application for a cap).
 
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Seems like a worthy addition. I wonder if the goal is to be able to charge in same or less time than ICE take to gas up. I guess we'll find out.

Ultracapacitors solve the problem with charging cycles and the speed of charging, however they are lacking in capacity.

The other problem is that even if they did have the capacity, and could be charged in 5 minutes to give you 200+ miles, how could you funnel that much power into a car in 5 minutes?

It would be like drinking from a firehose.

Just think about it. You have an electric car with a 50KWH battery that gives you around 200 miles.
If you wanted a full charge in 1 hour, you would need to supply it with 50kw's of power. That would be 480 volts at 100 amps.
If you wanted to charge it in 6 minutes (assuming you could), you would need 500kw's of power, or 480 volts at 1,000 amps.

Most homes in the US have 240 volts at 100 or 150 amps. That's 24kw or 36kw for the entire home.

How are they ever going to scale this to a car with a 600 mile range, or a large SUV with the same size battery pack and only a 250 mile range (150kwh battery pack)?

FYI: Tesla's super chargers can supply a max of 120kw per car, or 65kw per car if 2 cars are connected to the same charger, even though most the battery packs can't be charged that fast.
With a 150kwh battery, even a super charger with only a single car connected would take almost 1.5 hours. With 2 cars connected you would be waiting over 2.5 hours.
Your typical 240 volt, 30 amp home charger would take 20+ hours to charge a 150kwh battery.
 
Maxell makes audio cassette tapes. Duh. (I'm old.)

I'm guessing that besides the electrode technology, they may also want to use ultracapacitors for more efficient regenerative braking energy recovery. They can absorb an incredible amount of energy quickly then dump it slowly to the battery pack.
 
Ultracaps/Supercaps have high discharge, great operating temp ranges, and charge endurance (their quantity of cycles), but very poor power density..
You mean very poor ENERGY density. They have fantastic power density :) . They could also use ultra caps as a buffer between the main battery and motors to deal with constant discharge/recharge from acceleration/regenerative braking. Charging a cap is generally more efficient than charging a battery. Not sure whether or not it would be worth the extra complexity and cost though.
 
For a home, 55 gal drum sized capacitors wouldn't be an issue... Also most here are forgetting, electric grid stabilization, im sure hure capacitors banks have a place there.
This is an excellent acquisition, and seems like a bargain. Hopefully it will be easier to get my hands on some ultra caps, seems some used ones hit websites and then supply dries out so on.
 
I can see supercaps taking the same place in an EV as the batteries do in an ICE hybrid. Allow the use of a lower max output battery pack while also shielding the batteries from the many partial charge/discharge cycles in urban stop and go driving.
 
For a home, 55 gal drum sized capacitors wouldn't be an issue...

They wouldn't be an issue size-wise but they would be a safety issue. I've seen large UPS's with capacitors the size of tall beer cans. When thy get old and explode they dent the side of the case and fill the room with a toxic smoke/film/stench. I can't imagine what a 55-gal drum sized capacitor would do if it developed an internal short. I'm imagining something like when a Terminator get's its power cell shorted...BOOM...mushroom cloud.
 
They wouldn't be an issue size-wise but they would be a safety issue. I've seen large UPS's with capacitors the size of tall beer cans. When thy get old and explode they dent the side of the case and fill the room with a toxic smoke/film/stench. I can't imagine what a 55-gal drum sized capacitor would do if it developed an internal short. I'm imagining something like when a Terminator get's its power cell shorted...BOOM...mushroom cloud.
Heheh true true, didn't think of that... Buried in the yard might be the way to go then... If anything goes boom, you end up with a hole for a pool, and a pair of soiled pants.
 
Maybe this is for California e-rodders. Supercaps. Like a nitrous bottle for e-cars. 5 seconds of extra-ludicrous.

8723437f8f182fae0f060fb3ca644358.jpg
 
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like this
https://electrek.co/2019/02/04/tesla-acquires-ultracapacitor-battery-manufacturer/

Maybe they're interested in applying this to their existing battery production:
The automaker might be more interested with Maxwell’s dry electrode technology that they have been hyping recently.

Maxwell claims that its electrode enables an energy density of over 300 Wh/kg in current demonstration cells and they see a path to over 500 Wh/kg.
...
They claim that it should simplify the manufacturing process and result in a “10 to 20% cost reduction versus state-of-the-art wet electrodes” while “extending battery Life up to a factor of 2.”

At such high battery production levels, 10-20% cost reduction could be a billion dollars in the bank per year.
 
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Ultracapacitors solve the problem with charging cycles and the speed of charging, however they are lacking in capacity.

The other problem is that even if they did have the capacity, and could be charged in 5 minutes to give you 200+ miles, how could you funnel that much power into a car in 5 minutes?

It would be like drinking from a firehose.

Just think about it. You have an electric car with a 50KWH battery that gives you around 200 miles.
If you wanted a full charge in 1 hour, you would need to supply it with 50kw's of power. That would be 480 volts at 100 amps.
If you wanted to charge it in 6 minutes (assuming you could), you would need 500kw's of power, or 480 volts at 1,000 amps.

Most homes in the US have 240 volts at 100 or 150 amps. That's 24kw or 36kw for the entire home.

How are they ever going to scale this to a car with a 600 mile range, or a large SUV with the same size battery pack and only a 250 mile range (150kwh battery pack)?

FYI: Tesla's super chargers can supply a max of 120kw per car, or 65kw per car if 2 cars are connected to the same charger, even though most the battery packs can't be charged that fast.
With a 150kwh battery, even a super charger with only a single car connected would take almost 1.5 hours. With 2 cars connected you would be waiting over 2.5 hours.
Your typical 240 volt, 30 amp home charger would take 20+ hours to charge a 150kwh battery.

I've often wondered if a hybrid charging solution would work: Start direct to battery charging and then toward the end (25-30% left) send power into a bank of ultracapacitors while you wait for the battery temperatures to cool down but can still drive off. Might cut charging time but I am not familiar with how linear the charging rate is for electric cars vs phone batteries, etc.
 
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