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[NEW2elec]

This sounds very interesting.  A new type of battery cell that is the world’s first three-in-one battery solution with integrated inverter, charging and battery-management functions.  So one battery cell doesn't kill the battery early and gets the tutoring it needs to be a better cell.
https://www.businesswire.com/news/home/20181206005723/en/Sigma-Cells-CES-Smart-Battery-Electric-Cars

And a nice little video.

[NEW2elec]

Nothing? Really?  Is it just too vaporware or am I not getting what they are talking about?
It seems to do away with a BMS the motor controller and the onboard charger and they say smaller lighter and cheaper.  Maybe they are factoring in the cost weight and size of the components they replace but still that works for me.

[Moto7575]

What is the benefit have having some general purpose electronic inside the individual battery versus pooling it for several batteries and having a system adapted to your need ?

[NEW2elec]

Well the only interview is in French so I would like to hear more about it from the source maybe there will be more out later.
But to your question the simple answer is no BMS, no charger, and no controller means no failed BMS, charger, or controller.   
I haven't heard of any controllers going out on Zeros but BMSs and chargers are about $800 when you replace them trough Zero.
Will these cells be more reliable? 
Oh course we can't say yet but the idea of replacing a few bad under preforming cells for around $100 seems more appealing to me.

[Curt]

IMO, these days anything that exists mainly in the form of a cartoon can be safely ignored.

But the idea of patching out individual bad cells (or short chains of cells) sounds good, like patching chunks of on-chip RAM to improve the yield. Maybe a set of MOSFETs with sensor circuits would allow that?

[NEW2elec]

But it's a happy little chip doing work. 
There is a display video on YT but in French showing them turning off a battery cell and a fan still going simulating a failed cell being bypassed.
The main company is Leti CEA Tech which seems to have their hands in a few different technologies. 
Maybe an English video review from someone at CES will follow we'll see.

[togo]

> Nothing? Really?  Is it just too vaporware or am I not getting what they are talking about?

Vaporware till an actual product is on the market.  Only then can it be fairly evaluated.

[Doug S]

I remember a few years back, seeing a company that wanted to design an integrated product containing a single solar panel, mounting system and inverter. The idea was you could buy them one at a time, install them easily, and parallel them as you went. It's an attractive-sounding idea because you don't have to buy a single high-power inverter up front with a big start-up cost, or big mounting racks for the eventual complete array of panels.

Nothing ever came of it, though. No matter how you cut it, the cost of many small inverters is always going to be much higher than a single high-powered one, so the total system cost would always be higher. You'd always come out better off investing in a complete system up front, even if you had to borrow money to do it.

I suppose with this system, there is something to be said for being able to limp home if a single cell dies, but why can't a single BMS handle that same function for each cell? It seems to me the same logic would still apply.

[Curt]

I remember a few years back, seeing a company that wanted to design an integrated product containing a single solar panel, mounting system and inverter. [...]
Nothing ever came of it, though. No matter how you cut it, the cost of many small inverters is always going to be much higher than a single high-powered one

Actually those are called microinverters and they're popular. Their average lifetime is more than 30 years, whereas a single large inverter has an average lifetime of only 10 years (according to the company that installed my 3KW microinverter system). The system is very robust since you might lose one microinverter once in a while and they're up on the roof easy to replace. The monitoring company can do that when the owner isn't home.

I don't think they would have recommended microinverters if they were much more expensive.

[togo]

Which microinverters do you use, Curt?

[Curt]

Which microinversters do you use, Curt?

They'd also have the capability to start small and scale up,
which is what I want to do on another project (my home has
the big inverter).

Mine are from Enphase and come with 10 years remote monitoring included.
https://enphase.com/en-us/products-and-services/microinverters

The other cool thing is that Enphase has an API that allows me to implement this:
https://solar.fishlet.com/


Curt's Photovoltaic System Statistics

Current power: 26 W (15 modules at 1.73 W/module)
Service: 2013-04-05 to 2019-02-18 (5 y 318 d)
Energy so far today: 13.194 kWh (879.6 Wh/module), daily average 15.96 kWh
Energy so far this week: 55.948 kWh, weekly average 112 kWh
Energy so far this month: 133.417 kWh, monthy average 486 kWh
Lifetime energy: 34.238093 MWh (61.6285674 hoover-dam-seconds), yearly average 5.83 MWh

[togo]

> The other cool thing is that Enphase has an API that allows me to implement this:
> https://solar.fishlet.com/

Oh, that's cool.  Can you show us the code?

[Curt]

Oh, that's cool.  Can you show us the code?

Sure! Well, at least, here is a simplified version of it:

<html>
<body>

<h2>Photovoltaic System Statistics</h2>

<?php
$url = "https://api.enphaseenergy.com/api/systems/871416/summary?key=xxxxxredactedxxxxxxxxxxxxxx";

$ch = curl_init();
curl_setopt($ch, CURLOPT_URL, $url);
curl_setopt($ch, CURLOPT_RETURNTRANSFER, 1);
$data = curl_exec($ch);
curl_close($ch);

$json = json_decode($data, true);
foreach ($json as $k => $v) {
        echo $k, " => ", $v, "<br />\n";
}

echo "<br />\n";
?>

<h4>(energy figures are in watts)</h4>

</body>
</html>