60kw hybrid system with 50 or so kw battery recommendations of who to buy from

[TrueNorthSolar]

How does your all integrated solar system operate?

Generally speaking, once you integrate battery and PCS comms, you're getting an interactive system where all devices are sharing and reacting to the data and messages each are sending over that bus (typically CAN but Modbus is the norm on large systems). Here are three great examples of the benefits of an integrated system:
1) Accurate battery info for the PCS to act on: Let's use SOC, every decent Li battery has a BMS that's calculating SOC based on VPC and current in real-time. The only means that an inverter has to approximate SOC is through a shunt doing coulomb counting (inaccurate with the tendency to drift), but usually, they're just making a guesstimate based solely on VDC at their terminals. If the battery can relay that status to PCS on a comms bus, the PCS can make decisions like genstart/stop, grid-sell, LBCO etc.. with accurate triggers.
2) System Monitoring: The PCS is and always should be the manager of system-level monitoring. They are the hub for all sources and uses of power, and this is why every decent inverter brand has a great cloud monitoring platform. Since the PCS owns the monitoring, it's critical that detailed, accurate battery data is collected and logged in that central monitoring platform. Again, without closing the loop, all you'll see for the battery is VDC and current that can be gathered by the inverter at its terminals. You won't get fault/warning history, device info like S/N, fw rev, SOC, number of devices in the array, etc...
3) Leader/Follower capability: Normally, it's the PCS acting on the battery, but when you've got comms integration, the BMS has the ability to set target voltages dynamically based on the real-time state of the cell block (cell spread, temp, SOC, etc...) which extends the life expectancy of the battery in the long-term and reduces recharge time but up to 40% within any single charge cycle.

Bottom line: systems need to be comprised of components that can communicate with one another.

 

[Kornbread]

Generally speaking, once you integrate battery and PCS comms, you're getting an interactive system where all devices are sharing and reacting to the data and messages each are sending over that bus (typically CAN but Modbus is the norm on large systems). Here are three great examples of the benefits of an integrated system:
1) Accurate battery info for the PCS to act on: Let's use SOC, every decent Li battery has a BMS that's calculating SOC based on VPC and current in real-time. The only means that an inverter has to approximate SOC is through a shunt doing coulomb counting (inaccurate with the tendency to drift), but usually, they're just making a guesstimate based solely on VDC at their terminals. If the battery can relay that status to PCS on a comms bus, the PCS can make decisions like genstart/stop, grid-sell, LBCO etc.. with accurate triggers.
2) System Monitoring: The PCS is and always should be the manager of system-level monitoring. They are the hub for all sources and uses of power, and this is why every decent inverter brand has a great cloud monitoring platform. Since the PCS owns the monitoring, it's critical that detailed, accurate battery data is collected and logged in that central monitoring platform. Again, without closing the loop, all you'll see for the battery is VDC and current that can be gathered by the inverter at its terminals. You won't get fault/warning history, device info like S/N, fw rev, SOC, number of devices in the array, etc...
3) Leader/Follower capability: Normally, it's the PCS acting on the battery, but when you've got comms integration, the BMS has the ability to set target voltages dynamically based on the real-time state of the cell block (cell spread, temp, SOC, etc...) which extends the life expectancy of the battery in the long-term and reduces recharge time but up to 40% within any single charge cycle.

Bottom line: systems need to be comprised of components that can communicate with one another.

That's nice and all, but ... with Voltronic Power products, which are the manu of many of the more popular diy SCC on this forum, and with most of the more popular server rack batteries, we'll just choose the eg4 brand since they are by far the most popular plug-n-play server rack battery on this forum, you are stuck with the backed in settings of the battery's bms. So, now we have a system that talks to one another but with jacked up, non-adjustable settings that takes the battery way up into the upper knee, where very little power is actually stored.

Why would I want my LiFePo4 batteries consistently charging over 57v? That is not going to increase battery life expectancy. Doesn't matter if I like it or not, the parameters are not adjustable if the system is allowed to communicate. Are there benefits to communication? Sure, and you have pointed out some of them, but as you will discover, especially at the diy $$$ level most of us here operate within, they are also caveats. What you are accustomed to installing, sure, things work and at that price level, they better work, but at the budget levels most of us here are operating within, things are not so cut and dried.

" ... every decent inverter brand has a great cloud monitoring platform. ... ". Have you spent time with most diy level solar electronics? It is why many of us use (third party?) software like Solar Assistant, to monitor our systems, and/or bms software we can monitor and adjust on the fly.

 

[TrueNorthSolar]

That's nice and all, but ... with Voltronic Power products, which are the manu of many of the more popular diy SCC on this forum, and with most of the more popular server rack batteries, we'll just choose the eg4 brand since they are by far the most popular plug-n-play server rack battery on this forum, you are stuck with the backed in settings of the battery's bms. So, now we have a system that talks to one another but with jacked up, non-adjustable settings that takes the battery way up into the upper knee, where very little power is actually stored.

Why would I want my LiFePo4 batteries consistently charging over 57v? That is not going to increase battery life expectancy. Doesn't matter if I like it or not, the parameters are not adjustable if the system is allowed to communicate. Are there benefits to communication? Sure, and you have pointed out some of them, but as you will discover, especially at the diy $$$ level most of us here operate within, they are also caveats. What you are accustomed to installing, sure, things work and at that price level, they better work, but at the budget levels most of us here are operating within, things are not so cut and dried.

" ... every decent inverter brand has a great cloud monitoring platform. ... ". Have you spent time with most diy level solar electronics? It is why many of us use (third party?) software like Solar Assistant, to monitor our systems, and/or bms software we can monitor and adjust on the fly.
View attachment 117556

Who’s better at monitoring? You, or a connected system of devices that speak and react to one another in real-time? You’re actually with or representing EG4, aren’t you? That sounds like a rehearsed defensive response. No BMS ever asks for 57VDC regularly, all they’re trying to do is to get to 3.4VPC. LFP cells can take a higher target VDC charging but the end point to a cell’s recharge is 3.4VDC. 16 x 3.4 is 54.4VDC cell block on a 51.2VDC (3.2VPC) battery.

 

[TrueNorthSolar]

I’ll add this after reading your last post: Voltronic power electronics are built by a good manufacturer who ODM’s for many other resellers. They don’t have carts to be NEC compliant and they don’t have any experience with north American grid or device handling. Here’s a test for you, see if their grid-forming inverter can do more than 60% of the total inverter capacity on a single leg. I’ll save you some time - it can’t because they’re a company that designs string inverters who’ve happened to make one that’s bi-directional.

 

[Kornbread]

Who’s better at monitoring? You, or a connected system of devices that speak and react to one another in real-time? You’re actually with or representing EG4, aren’t you? That sounds like a rehearsed defensive response. No BMS ever asks for 57VDC regularly, all they’re trying to do is to get to 3.4VPC. LFP cells can take a higher target VDC charging but the end point to a cell’s recharge is 3.4VDC. 16 x 3.4 is 54.4VDC cell block on a 51.2VDC (3.2VPC) battery.

Sorry, but you are wrong ... again.

 

[TrueNorthSolar]

Sorry, but you are wrong ... again.

Take your stance. I’m just a guy who’s been designing, managing and selling battery-based hardware and systems around the world for 20 years.

 

[Kornbread]

Take your stance. I’m just a guy who’s been designing, managing and selling battery-based hardware and systems around the world for 20 years.

Figured that much. See post #22. You have a lot to learn about the diy aspect of this hobby.