New Idea For Tesla Battery Storage...

[murphylawe]

Howdy Everyone,

I have enjoyed my Solarsaurus Rex, and the Solar Gantry (Pat. Pend), the ability to run A/C and refrigeration on solar power in the desert has been liberating. That said, I have pretty much killed the (8) 12v AGM battery stack over the last 2 years.

So, now that I have a proven design I will be upgrading the stack to lithium. I have been observing the falling prices for 3.2v-280ah cells with interest. I will need 16 of them, so about $4000.

For the same price I can get 6-Teslas (I have a friend)... and nothing on Earth beats the Tesla for performance/price. I have a solution for the BMS, but that is only half of the problem. Additionally I need an inverter that will function within the operating parameters of the Tesla stack (25.2v-18v) most inverters kick at 20v, so you leave a bit behind. Victrons can be programmed to kick at 19, still leaving some, and they are a tad pricey. With an AIMS 4000w I am stuck with the pins...

So, I was just about to commit to an LiFePO4 battery cell order when I ran across this... and my head exploded.

DIY Cheap 1000W Pure Sine Wave Inverter (12V to 110V/220V)

DIY Cheap 1000W Pure Sine Wave Inverter (12V to 110V/220V): Car batteries for powering you home? Build a low cost 12V to 220V (DC-AC) Pure Sine Wave Inverter from scratch! The project is based on the low cost EGS002 SPWM driver board module. The DIY inverter board can handle up to 1kW (depending...

www.instructables.com

HOLY SMOLY!!! I never even considered it... too busy with other stuff, but now with Fall and the maintenance cycle beginning... Has anyone in this forum built an inverter? How about an inverter/charger? Can I tweak a DIY inverter/charger to operate within the Tesla parameters of 25.2v-18v?

I am not an engineer, or an electrician but I want to build a 5000w inverter/charger... I play with Arduino, with some advice and encouragement I may explore this. I need to be talked into, or out of this insanity.

 

[jwu_cc]

Sigineer does have some inverter/charger that cuts off at 18V to support Tesla battery modules: https://www.sigineer.com/product-ca...rs/tesla-battery-compatible-inverter-charger/. There are a few rebranded ones on the market as well if you want to shop around for price or support. The 6KW version is about the same price of a Multiplus, but you do get double the inverting power plus it's split phase ready to support 240V applications if you have a need for it.

 

[murphylawe]

Holy Schittt!!! Gotta go scoop my britches... I love a ready-to-go solution.

 

[Lt.Dan]

So, now that I have a proven design I will be upgrading the stack to lithium. I have been observing the falling prices for 3.2v-280ah cells with interest. I will need 16 of them, so about $4000.

I think you need to shop around more. I just bought 16 from Michael for under $2000.

I do not think the other problems that come with Tesla packs make it worth it. Stick with the DIY cells.

 

[Texas-Mark]

Has anyone in this forum built an inverter?

Many years ago I built one (pure sine wave) with just a few parts, some power transistors, and a transformer (wired in reverse). It did not provide much power, but it worked.

 

[eXodus]

I think you need to shop around more. I just bought 16 from Michael for under $2000.

you a need BMS for those, Build a case for compression. Install busbars etc. for 14kwh.

When you got all this - you are at 3X the weight, and the DIY take up much more space.
Further the Tesla modules have watercooling - so when you toy around with that - you can add a reservoir and get them working below freezing.

You can sometimes grab Tesla modules with 5.xx kwh for less then $1000.

Then add one of those 3000w

3000 watt Tesla Lithium Inverter Charger 25.2v 6s

This is a 3000w ALL CURRENT COMBINATION Inverter Charger. This means it can use any battery type at 24v system. Lithium, Lifepo4, Lead Acid, AGM etc. This is an one for all battery type inverter charger.

solargeni.com

I'm not saying Tesla S cells are ideal, certainly not, but there are use cases for them - especially now when you get of the shelf inverter/chargers which support them. Setting the maximum charge voltages at an decent MPPT is easy.

 

[cedarshoot]

Can anyone provide the BMS info for a Tesla S/X module?
Thanks

 

[dougbert]

Can anyone provide the BMS info for a Tesla S/X module?
Thanks

This the BMC (battery manager controller for the tesla indivual BMS boards)

I installed one on my system

build thread at https://diysolarforum.com/threads/something-i-built-diy-back-in-2000-on-my-house-and-it-shows.11/

 

[Jennifer]

I installed one on my system

build thread at https://diysolarforum.com/threads/something-i-built-diy-back-in-2000-on-my-house-and-it-shows.11/

If you're even considering using Tesla modules you need to read Doug's build thread, from start to finish, memorize it, read it in your sleep, put it under your pillow, then when you've finished, do it again... then toss him a few bucks via paypal for all the hard work he put into it.... it is and he is the bible/god when it comes to this system... especially now that Jack is no longer with us....

Jen