New Off Grid Inverter Charger

[onanparts]

Stopped by Midnite today. Robin was not around so I could not get any answers concerning what appears to be at least four MNB17-5 Inverters that look to be ready for shipping? As you can see they are partially boxed up etc. I asked somebody in the area if they knew what was up, and the reply was they are possibly in house/employee use only Alpha units!

Three were loaded up with modules and one was a bare unit. I know they have some folks that work for them that are out of state so maybe that's where they are going? If these are actually Alpha units then those of us interested in the Beta units may not have too much longer to wait!

Spotted an interesting support bracket for the B17. The wall mounting plate is thick and looks very strong so maybe these are for added support when stacking. It looked kool so I grabbed a pic. 

[onanparts]

Also got a pic of this PV array at MS. This is one of several they use for testing. Next trip up I hope to be able to plug in my EV to a battery based B17 that gets it's juice from this array.  Charged by the sun at home and when visiting MS!

[Sunshine]

We do enjoy letting the rumors fly but unfortunately those are not finished units for our out of state folks. Those are our show models, back from Intersolar and getting ready to ship out to SPI. Rest assured though, we are hard at work, making sure that we will have some fun new features to debut in Las Vegas.

[Robin]

Quick B17 update.
Inverter power modules very well may exceed 2KW. Our limitation is no longer the transformers. They are running pretty cool now.
Communications between the MNGP, Justin's controller board and Bob and Mario's power modules is starting to work. We expect to demonstrate this at SPI.
I am ecstatic regarding the B17 progress during the past month or so.

I am now working on a plug in Lithium battery pack to go with the B17. My goal is to make a plug in that just slips into an unused slot in the regular B17 and then to also offer a similar B17 mainframe that would hold 7 battery packs. The battery pack face will look just like the MPPT and Inverter face plates.

[Westbranch]

Robin said:  The battery pack face will look just like the MPPT and Inverter face plates.

Robin, how will the uninitiated know if he is getting the B - 17  controller/Inverter pack or the Battery Pack? Just has to be able to count past 5?     

[Robin]

I don't have any good pictures here at home, but each module face says MPPT or INV. The meter faces inside the meters are specific to which type of module they are too. We put a raised rectangle area on the bottom of the module face specifically to add a label stating what the module is because at a glance you cannot tell. Once you actually look at them, it is easy to determine just what it is though. I don't know what we will do for the battery face plate yet? I do want to keep the basic look the same though. Single meter, push button and a couple of leds. I don't know just what the push button or leds will do yet? I suppose the meter will read voltage and one of the leds will verify voltage. Maybe when you push the switch, it can read current. Then the other led would switch on. This is how the other power modules work. I will get some close up pictures of the meter faces and module faces and post them.
If you want to check the health of each battery string, it will be available through the MNGP. We are attempting to put 104 #18650 Lithium battery cells in each module. Those would be two strings. Each string is comprised of 13 cell groups. Each cell group would be 4 of the #18650 cells. Those are a bit larger than a AA battery. We have cooling air, so if we can fit 104 batteries and the BMS system in our module size, we can keep them cool. It is very cramped though. Give me a few more days and I should know if this many batteries is possible.

[ClassicCrazy]

Robin ,
This is a good book on building lithium battery packs out of 18650 cells - Micah knows his stuff
https://smile.amazon.com/dp/B06XRKD15B/ref=smi_www_rco2_go_smi_g2609328962?_encoding=UTF8&btkr=1&ie=UTF8

Larry

[Robin]

Thanks, I have requested three Lithium books already, so this will be the fourth.
This battery pack is going to be a fun project.
I had Rob Ruth take some photos of meters and module faces this morning, so I will post them here. I hope it begins to clear up some of the mystery about the B17.
These four pictures show the three meters on the E-Panel side of the B17. The bottom two are for each AC input. The top one is the AC output. There will generally be only two on at a time. They should match, so if they don't, this will give you a clue.

The module front is Justin's control module. I call it the traffic cop. It connects to everything. It has it's own meter (meter1 photo). That meter just shows you bat volts, current coming or going or state of charge of the battery. All of these are available on the MNGP too for those millenials that don't like analog meters.
The fourth photo is Mario's MPPT faceplate. You can see it has a raised PV label. The inverter module says VAC in the same place. This is where we can also say something different for the lithium battery pack. I don't know what to say though. We have no restriction on layout of the battery faceplate, but I was thinking it would be nice to make it match the other power modules. I am open to suggestions though if you can come up with different ideas that lend itself to this battery module.

[Highflyer]

Robin,
Has there been any thought or discussion about using the newer 2170 batteries for a lithium battery pack?

According to the press, it has more energy, and will cost less.  Just curious.  Keep up the great work.

[bailey]

I haven't seen any comments on which Lithium battery chemistry might be used?

Based on current popular options I recommend you investigate Lithium Iron Phosphate (LFP), cells.  Not as energy dense as NMC or some of the other formulations, but the combination of excellent lifespan and safety characteristics seems like a good "impedance" match for a MidNite Solar product.

It also differentiates you from LG & Tesla which I believe use NMC.  I personally don't want to be anywhere near one of those systems if the BMS electronics glitches!

Cheers,

Kirk Bailey
Abundant Solar, LLC.

[Robin]

Those are all good comments. I will investigate.
Thanks,
Robin

[ClassicCrazy]

I haven't seen any comments on which Lithium battery chemistry might be used?

Based on current popular options I recommend you investigate Lithium Iron Phosphate (LFP), cells.  Not as energy dense as NMC or some of the other formulations, but the combination of excellent lifespan and safety characteristics seems like a good "impedance" match for a MidNite Solar product.

It also differentiates you from LG & Tesla which I believe use NMC.  I personally don't want to be anywhere near one of those systems if the BMS electronics glitches!

Cheers,

Kirk Bailey
Abundant Solar, LLC.

Here is some testing on various lithium types
https://youtu.be/dree0rTr1HM

Larry

[Robin]

Yup, Lithium can be very dangerous. We plan on monitoring the temperature of every single cell.
That helps a lot.

[Sunshine]

I would like to remind everyone that we will be conducting a very important test on the B17 today. It is vital to it's release. If you are in North America, you will experience partial to full obstruction of the sun over an approximately 2 hour period. Please do not be alarmed. The sun will return to normal as soon as our tests are concluded. Thanks!

[ClassicCrazy]

I would like to remind everyone that we will be conducting a very important test on the B17 today. It is vital to it's release. If you are in North America, you will experience partial to full obstruction of the sun over an approximately 2 hour period. Please do not be alarmed. The sun will return to normal as soon as our tests are concluded. Thanks!

We hope the thing doesn't burn out !