192V/60S

[Mentalis]

Thank you @Will Prowse for the forum.

I have a 208V inverter from APC, SURT10000XLT. The DC input voltage is 192V, and have 2x APC SURT003 giving 120, 208, and 240 output from the inverter. I'm looking to build a battery pack and I see lots of options, so far I've settled on purchasing 16x (for now) of the Zooms/Chins battery packs. It seems the cell quality is good, they each come with a BMS, but I see the packs I linked as manufactured come with a 48V limit. Obviously this is a limitation of the BMS (true?), but for the price it seems good for the cells.

Really I'm just here for hardware suggestions.
This will never be grid tie, but it's pretty high voltage so I'd like some second-hand experience before I get more involved or do something uneducated.

I plan to run my well (1HP) and pool pump(0.5HP), the pool water will be lightly pressurized against the back of the PV panels using some soft PVC.
I also have a 208v-25amp multi-zone split system for A/C and some 1200-2400w 120v temp controlled in-line water heaters.

Could anyone offer some BMS recommendations (EV based?), PV charging approach, alternate cell recommendations?

Thanks in advance.

EDIT (minutes later):
I've found these 280AH 3.2V cells with studs from watching one of Will's videos. For 60S, can I set up 4 banks of 48V with some high-amperage BMS and be "okay"? It seems the max current would be ~75A, but what limits the circuit voltage with these batteries?

 

[Samsonite801]

I have a SURT5000XLT and a SURT6000XLT (the 6000 is installed in the trunk of my 2018 Prius, used as a power source / generator (along with the SURT003 transformer)...

I have looked into this as well a bit, on how I could hook up more batteries if desired. The best option I have come up with is most likely this BMS:

123\SmartBMS gen3 - 123electric

123electric.eu

Supports up to 255 cells if you buy more modules. I thought I had figured I needed 56 cells of LiFeO4 for this... I was even thinking of adding LiFePO4 cells to the car to add EV capacity (since Prius hybrid has an EV-only button on the dash)...

I have bigger fish to fry for now, since I have a set of MPP LV6548 inverters to use on my off-grid house project, so this stuff I have now with the APC in the car as a power source is fine as it is for me, and I already use the car a lot as a generator only to give me power when I'm out working at the storage unit or on the property, so I doubt I will get back to trying out the 123 Smart BMS, but you never know, we'll see...

 

[Samsonite801]

BTW, on the SURT6000XLT (and 5000), you can change the output voltage on the inverter unit up to 240v in the settings on the SSH/Telnet CLI menu (access via IP over the onboard LAN module and Ethernet), and there is a physical switch you set to 240v input on the SURT003 if you want to use standard AC voltage for US... My guess is the SURT10000XLT would allow to change it to 240v too?

You have to change it in both places, the inverter via CLI menu, and on the transformer input physical switch...

 

[Samsonite801]

EDIT (minutes later):
I've found these 280AH 3.2V cells with studs from watching one of Will's videos. For 60S, can I set up 4 banks of 48V with some high-amperage BMS and be "okay"? It seems the max current would be ~75A, but what limits the circuit voltage with these batteries?

Also BTW, 75a is a lot considering the high voltage DC, remember as the volts goes up, the amps goes down. On my Prius, I calculated around 25a of draw, so I put 30a fuses on my DC wire (first picture above) connecting to the Prius battery and I've never blown them. If I try to start my big 4 hp 14.5a 240v air compressor it trips my inverter first.

I considered trying a SURT10000XLT to see if it would start that thing. I even tried putting a soft-starter on the compressor and it tries to turn it now but still trips the SURT6000XLT after about 5 seconds in... It runs my chop saw, drill press, miter saw and small compressor fine though.

I would guess your SURT10000XLT would only draw up to 50 or so amps off the DC bus. You could test it with an amp-clamp probe to be sure...

 

[Mentalis]

Very interesting seeing the inside of the SURT003.. I expected it, but dang that's a huuuge coil. Well, I wasn't able to buy batteries. Lol, I could maybe get 192v using 18650s right now.

I will go for your SmartBMS suggestion, if you have anything else please let me know

 

[Samsonite801]

Very interesting seeing the inside of the SURT003.. I expected it, but dang that's a huuuge coil. Well, I wasn't able to buy batteries. Lol, I could maybe get 192v using 18650s right now.

I will go for your SmartBMS suggestion, if you have anything else please let me know

Yeah that SURT003 is heeeeeavy!

 

[Mentalis]

I have still not purchased batteries for this UPS, I still intend to use it as an off-grid inverter. I believe the battery input voltage is 192v at the board. Still have not planned any further. Does anyone have experience with the 10kv model?

 

[Rocketman]

You cannot hook several standard 48v bms’s up in series - I believe the FET’s in them will be fried at the higher volts.

I use a Batrium bms on my MotorHome (I wanted a high amp solution), but it can be used with high voltage.

I have been thinking about a 96v battery or a 144v battery (for an electric powered boat) and that is the bms I would use on it. My thoughts are for each 48v pack have a Tyco EV200AANA contactor (Relay) break the interconnect wire between the packs - that way with a switch I am back to 2 or 3 48v batteries for maintenance.

The bms would be the Watchmon core and then a Cellmate K9 for every 16s segment (48v).

Anyway Good Luck with your project.
Be safe around the high DC voltage.

 

[Mentalis]

Sorry, I may have been mistaken. The SURT10000XLT from APC apparently takes two 192v lines in series for 384v? Could it be +192, 0, -192?Batteries for this UPC are always sold in pairs and I never had access to original packs to inspect. If anyone knows, count me Lost and trying not to cause failures. I would certainly like to avoid use of a BMS and find another way to manage cells if possible. I need to study more.

Will certainly be wearing dry leather around anything I do with this project.
I'm 100% sure I have no idea what I'm doing and would be thankful to work with some folks who do.

 

[Samsonite801]

Sorry, I may have been mistaken. The SURT10000XLT from APC apparently takes two 192v lines in series for 384v? Could it be +192, 0, -192?Batteries for this UPC are always sold in pairs and I never had access to original packs to inspect. If anyone knows, count me Lost and trying not to cause failures. I would certainly like to avoid use of a BMS and find another way to manage cells if possible. I need to study more.

Will certainly be wearing dry leather around anything I do with this project.
I'm 100% sure I have no idea what I'm doing and would be thankful to work with some folks who do.

Yeah, the SURT10000XLT input is 384v nominal...