Tesla Wants to Build a Battery for Your House

[Jerry Liebler]

tesla powerwall

https://en.wikipedia.org/wiki/Tesla_Powerwall

With the small charge and discharge currents (less than 0.5C) I'm surprised they need liquid cooling. I was wrong, the voltage is 350-450 & price is $3500 for 10kw.
To build a similar, but much safer, battery I'd use 130, 24AH LIFEPO4 cells. The challenges are the DC to DC converter & communication to the Solaredge inverter.

[SunEagle]

https://en.wikipedia.org/wiki/Tesla_Powerwall With the small charge and discharge currents (less than 0.5C) I'm surprised they need liquid cooling. I was wrong, the voltage is 350-450 & price is $3500 for 10kw. To build a similar, but much safer, battery I'd use 130, 24AH LIFEPO4 cells. The challenges are the DC to DC converter & communication to the Solaredge inverter.

That 10 kw system is also designed as a "backup" power source and can't be discharged on a daily basis. It comes down to being a very expensive generator that can run a few hours maybe a couple a days a week at most. Much cheaper to get a whole house emergency generator which will last longer and provide much more in the way of kWh each time it is used. ------------------------And yes based on Tesla's battery chemistry they need to use cooling or those puppies will over heat and probably cause a fire.

[ButchDeal]

more info from SolarEdge on the arrangement of disconnects etc:
http://www.solaredge.us/files/pdfs/p...tasheet_na.pdf

[inetdog]

more info from SolarEdge on the arrangement of disconnects etc:
http://www.solaredge.us/files/pdfs/p...tasheet_na.pdf

One detail I find interesting is that they include an external autotransformer in the design so that the standard 240V output of the inverter can be connected to a split phase 120/240 three wire system. It appears that that transformer is part of the base price of the system.
For a pure GTI the balancing of the two legs to provide for 120V loads would be the responsibility of the grid.

[ButchDeal]

One detail I find interesting is that they include an external autotransformer in the design so that the standard 240V output of the inverter can be connected to a split phase 120/240 three wire system. It appears that that transformer is part of the base price of the system.
For a pure GTI the balancing of the two legs to provide for 120V loads would be the responsibility of the grid.

It is optional and only required if backup is required. If you only want to load shift it isn't needed

[inetdog]

As of today, Tuesday, March 22, 2016, Tesla has apparently discontinued the low cycle 10kW storage Power Wall model. Sales were not high enough to justify it, since apparently nobody saw any good use for a battery with less than 50 cycles before end of life.
No announcement on whether a re-engineered large battery pack is in development, so for now the high capacity solution is two or more of the smaller 3000 cycle units.

[inetdog]

That 10 kw system is also designed as a "backup" power source and can't be discharged on a daily basis. It comes down to being a very expensive generator that can run a few hours maybe a couple a days a week at most. Much cheaper to get a whole house emergency generator which will last longer and provide much more in the way of kWh each time it is used. ------------------------And yes based on Tesla's battery chemistry they need to use cooling or those puppies will over heat and probably cause a fire.

Looks like the market agreed with you.

[SunEagle]

Looks like the market agreed with you.

Actually that is sad news. I really wanted them to perfect the system and get the price down so us joe blows could afford one.

I understand that the new battery plant in Nevada is producing (or assembling) the smaller 6.4kWh PowerWall system. There is also a number of places like Australia and Germany that are really interested in getting those battery systems so Tesla may see the light at the end of the tunnel.

As long as that light isn't another train coming at them.

[inetdog]

As long as that light isn't another train coming at them.

Or, as Mark The Radical said to a senator in the Doonesbury comic strip, "I don't see how you can keep digging yourself deeper into a hole and calling it a tunnel."