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Discussion: Powerwall 3 [Speculation / Discussion etc]

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(Moderator note)

This thread contains both pre release speculation, as well as confirmation of the first install reported by a TMC member. To Jump to the beginning of the "confirmed install" discussion, I suggest jumping to the following post in this thread (post #146), and reading from there:



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There has been speculation about Powerwall 3 for a long time but the discussion seems to be gaining some momentum as shown in the article below.
As the facts emerge it will be interesting to learn some of these details.

  • Release date (and actual general availability)
  • Pricing
  • Capacity (and other specs)
  • Battery chemistry
  • Can it be added to PW2 systems (say add 2 PW3s to an existing 2 PW2 system)
  • Is the physical size the same so it can be stacked with PW2
  • Inverter (rumors say the inverter will be internal as opposed to the external module on a PW+)
  • Will PW2 still be available or will the PW3 replace it
 

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I'm hoping for this information release soon. Currently waiting for permitting to clear with the city before having two PWs installed. Can I insist on having a particular model (i.e. PW3), especially if it's cheaper?
Nobody knows, but I find it pretty unlikely that a PW2 project could be switched to a PW3 without completely redoing the permitting, engineering, etc. if anything is substantially different - storage capacity, max charge/discharge rates, etc - you’d basically need to start over.
 
Prismatic cells suck, there are forces pushing plates apart while discharging; require clamping and are bigger fire risk then cylindrical cells…. Tesla needs to walk carefully, if a fire happens then code will further restrict installations, they need to stay conservative with powerwall.
 
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Prismatic cells suck, there are forces pushing plates apart while discharging; require clamping and are bigger fire risk then cylindrical cells…. Tesla needs to walk carefully, if a fire happens then code will further restrict installations, they need to stay conservative with powerwall.
Are you sure you aren't thinking of pouch cells? Tesla currently uses prismatic LFP cells in their "standard range" vehicles and prismatic LFP cells are used heavily in many ESS also. Prismatic LFP cells have generally been viewed as some of the safest cells there are.
 
Indeed prismatic cells are inherently more of a fire risk than cylindrical, but LFP chemistries are vastly less combustible than typical Nickel-based chemistries. So much so, that even a simple pouch LFP will still be much safer than a cylindrical NCA.
Exactly and the current Powerwall uses cylindrical NCM cells. Almost all ESS are using prismatic LFP cells these days.

Cheap, safe, and long cycle life.
 
What I got out of that article is, was cheaper for tesla to produce, same storage capacity as current powerwall 2s, but more burst power output (meaning you could drain them even faster than you can now, but might have less issue starting up equipment with high initial draw).

I was hoping for something with more storage in same size. Its not like tesla is going to drastically reduce price when they make it cheaper for themselves to produce it, its just more profit.

Im also not a huge fan of the LFP model 3s but thats because people point to "I can charge it to 100% all the time" as some sort of benefit there when that really doesnt matter in day to day usage, at least for most people. Its just less mental worrying about it for them to charge it to 100%, it doesnt actually change the way most people will use the vehicle.

On battery storage the "charge to 100% all the time" thing means more, of course, and perhaps these have longer longevity, but I still see what is presented as "cheaper to produce" first and foremost.
 
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On battery storage the "charge to 100% all the time" thing means more, of course, and perhaps these have longer longevity, but I still see what is presented as "cheaper to produce" first and foremost.
These are the main two points for me.

Cheaper ESS is needed just like cheaper EVs are needed for more mass adoption.

Powerwalls also sit at 100% a lot of the time from what I've seen and cycle life is very important for longevity, especially when you can't tell the Powerwall to only charge to 80% for example.
 
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These are the main two points for me.

Cheaper ESS is needed just like cheaper EVs are needed for more mass adoption.

Powerwalls also sit at 100% a lot of the time from what I've seen and cycle life is very important for longevity, especially when you can't tell the Powerwall to only charge to 80% for example.

I agree that cheaper ESS is needed, but dont have any confidence at all that "cheaper to produce" is going to translate to cheaper to the customer (lol).
 
Indeed prismatic cells are inherently more of a fire risk than cylindrical, but LFP chemistries are vastly less combustible than typical Nickel-based chemistries. So much so, that even a simple pouch LFP will still be much safer than a cylindrical NCA.
I just don’t want to see fires. Insurance and government will reject them if fires start occurring. I would like the industry self regulate themselves rather then have the government step in. So far powerwall is a unicorn, lets keep it that way.
 
Lol...so your contention is they charge to what 97, 98, or 99% of cell capacity? Still the same point.

When I queried my installed powerwalls shortly after they were installed, they had a capacity of 14.5kW each. I dont think 100% on a powerwall is actually 100% of its storage capacity. I still believe LFP would just help lower teslas costs because they wouldnt install as much (or any) buffer, making it cheaper for them but no different for the customer than it is now.

You can query your powerwalls and see what the installed capacity is.
 
I thought the Powerwalls had a feature where you could tell them to prepare for an apocalypse or something? Maybe that's the only time they go to 100%?

Or maybe they just don't hold 100% for very long. It's not so much the peak charge that ages cells as it is the length of time spent at that high SOC. So if they hit 100% in the late afternoon and then start draining back down the moment your house consumption exceeds solar output, it might not be so bad to go to 100% daily.