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**CountryFit** · 02-12-2015, 01:26 AM

i have been closely watching tesla's move on lithium batteries, now it's official -
“We are going to unveil the Tesla home battery, the consumer battery that would be for use in people’s houses or businesses fairly soon,” Chief Executive Officer Elon Musk said during an earnings conference call with analysts Wednesday. Musk said the product unveiling would occur within the next month or two.

This is a good news for rvers who intend to upgrade their house batteries....
Here is the news report: Tesla Plans Battery for Household Energy-Storage Market - Bloomberg Business

Bigd9 · 02-12-2015, 05:10 AM

Interesting. No information about price or size of the batteries. I also wonder about the safety of using lithium batteries. There are some real scary fires reported to be caused by lithium batteries shorting out.

wa8yxm · 02-12-2015, 05:38 AM

I too noticed a lack of anything useful in that article.

That said, if anyone can do a better job of it, they are likely the ones.

**CountryFit** · 02-12-2015, 09:12 AM

i am guessing the lacking of specific info on the batteries has to do with the nature of the meeting - it was a company earnings conference, not a new product announcement meeting. the details will be handed out in an "unveiling" event in "next month or two".

though no details, i am sure it wil be lifepo4 type batteries - iron phosphate based - which is being massively used in hybrid/ev's, the safest among all types of lithium bateries. we don't hear a lot fire incidents on prius or leaf. as for shorting circuit, sure it will be dangerous, just like any batteries shorting could be deadly, it is not lithium unique. when lifepo4 is installed, a pcm is recommended as it will cut off the connection in the event of short, over charge and over discharge.

nothermark · 02-12-2015, 10:02 AM

A failed PCM could lead to a shorted battery. It's the nature of the beast. Fuses and circuit breakers are protection devices assuming the short is after the protection device.

FWIW The only difference between energy stored in a battery and energy stored as a liquid or gas in a tank is the mechanism needed to set it off. The Lithiums that were self combusting were the equivalent of making the fuel tank out of a slow dissolving plastic and putting it next to the pilot light ignited heater. Given time and drip drip boom. Bad chemistry strikes again.

Hugmongous · 05-09-2015, 01:27 PM

Could be a real game changer if Tesla made a battery for the RV market. Tesla battery bank + solar =

Tesla has announced the opening of a battery factory in Nevada and also the powering of WalMart, Target stores and Amazon warehouses with the Tesla batteries packs.

Tesla pushes its batteries beyond cars - LA Times

Reed Cundiff · 05-09-2015, 06:03 PM

The voltages are rather high to charge with solar unless you get one heck of a lot of panels in series. Panels could be designed to give such voltages. Son tells me that DC voltages from battery suite above 50 V nominal require different Nation Electric Codes (NEC)

ObscurAbode · 05-10-2015, 11:09 AM

The tesla battery pack made specifically to charge from home solar panels may require too many for most RV users, but I am watching too. We should write in and tell them we want an RV version. I am sure of enough people expressed interest they would make one if it's doable. And with the tesla design it seems it would be! There are people using solar panels already on rVs so this shouldn't be too much of a stretch

nothermark · 05-10-2015, 04:06 PM

FWIW higher voltages are preferable because wire sizes and heat related losses are current dependent. The higher the voltage the lower the current for a watt of power. In terms of battery banks a stack of smaller cells is that can be replaced individually makes a lot of sense.

Early life failures can be dealt with simply instead of doing a wholesale replacement. It may even be reasonable to have self testing cells with automatic power shunting and a failure flag. That way a bad cell takes itself off line and triggers a warning for maintenance. Changing one then gets as simple as changing a circuit breaker. The inverter and charge controller can both be designed to compensate.

The solid state converters available today are pretty efficient at moving the voltages around as needed by the load. The wiring will essentially be the same as the AC wires commonly in use now. As I recall that is specified for 600 V or so.

wa8yxm · 05-10-2015, 04:16 PM

The voltages on the new Power Wall batteries are kind of not something we can use...Directly.. Nor will the battery fit in most motor homes (though you could build one in on a new one)

I can think of a way to make it more practical.. Basically I'd use it as part of A "power Line Conditioner" set up.. what is a Power line conditioenr?

Unconditiond power mains--Converter---Battery--Inverter--Conditioned power.

The converter could be designed to operate over a wide range.. Say 70 to 300 volts in. Thus solving most camp ground power issues... Of course you may find your power wall running down in the heat of the day (30*90 is still less than 30 * 120) but you'd not be worrying about A/C and elctroncis, And if you plug into 240 by accident.. Well most switching power supply type converters can handle that.