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New 48 volt rack battery specs-what do you want to see?

Bluedog225

Texas
Joined
Nov 18, 2019
Messages
2,830
Good morning,

I was having a conversation with Amy about the possibility of her company developing and selling a 48 volt rack battery. She seemed interested and was going to have some prototypes developed.

I was typing up a response to show her Will’s review of the EG4 so they could learn from the review. I also wanted to start a new thread so we could all contribute to describing what we would like to see in a budget, 48 volt rack battery. E.g.: fused, welded or bolted, low-temp cutoff, etc. And maybe some tips to avoid the Signature Solar issues.


But I was unable to post this response to Amy. And now I cant find the thread. Maybe I just need mor coffee this morning but I think I just happened to post as the new policy was coming in.

I’d like to have an open discussion with Amy about developing this new product. But the new policy states: “Vendors cannot post self-promotion content or material in posts or in their profile. This includes prices, deals or marketing material.”

Part of the purpose of this post is a trial balloon to see if Amy, or other vendors, would be prohibited from participating in this type of discussion.

And I think it would be good to list the attributes of a budget 48 volt battery we would like to see.

-Rack configuration
-48 volt
-bolted terminals (user serviceable)
-circuit breaker
-low temp cutoff
-communications (which ports; which protocols?)
-capable of parallel operation
-bluetooth?
-other
 
Nothing in the way of the terminals so that bus bars can be screwed right too them up/down a whole rack.
Also wall mounted as an option.
 
Vibration padding so they can be used in vehicles better.
Series connection support for upgrading later?
12v and 24v versions!
Rack configuration optional - removable/rotatable/moveable mounting ears
 
Hi! I'll be following this thread as well so we can try to improve our products.
Nothing in the way of the terminals so that bus bars can be screwed right too them up/down a whole rack.
Also wall mounted as an option.
How would you wall mount a server rack unit? Curious about your thoughts on this!
 
How would you wall mount a server rack unit? Curious about your thoughts on this!
Have the tab ears screwed to the case with mounting holes so the tabs could be rotated and screwed 90deg off to go to the wall standing vertically. For bonus, add pre-threaded holes near the bottom of the case so you can have 2 sets of ears/brackets top and bottom.
 
Or just provide matching holes that are centered, for wall mounting vertically.
This wall mounting idea is growing on me.
I am imagining how useful this could be.
 
Now,
I want the wall mounting option to provide space between the wall and battery. For good air flow and a space to run the wiring. This would make for a neat installation.
 
The batteries are always what takes the premium space. I may design a wall mounting system for my future server rack battery expansion.
 
I wonder if some sort of STRONG french cleat system would be ideal since then you could make sure everything is level.
That's how EnergeTech does theirs - French cleats on the back/bottom side, ships with matching brackets and concrete anchors.

They position the BMS screen on the opposite side to allow it to be visible when mounted this way, which makes it awkward for racking; less of an issue if you're monitoring via CAN or RS485 I suppose.
 
Does anyone know how to summon the various chinese manufacturer representatives? Is typing e.g.: @Bluedog sufficient? I’ve seen others do it but didn’t pay attention.

While they can’t promote, I wonder if they could let us know they are looking at this list. Or ask clarifying questions.
 
Looking at this list and I think the "Budget" part has flown out the window. :)

If I were looking for budget models, I think I'd start with "What do others have that I can lose?" and go from there.

I think the first thing I would give up is all the communications ports. If the battery turns on and provides power that's all I'd need. Maybe a BT module as those a re really cheap but again, all I really need is it to power on and provide power.

After that would be any kind of anti-theft (**COUGHCOUGHJAKPIERCOUGHCOUGH*) or position monitoring system. Actually, might start with that.

The next thing I'd lose would be any kind of pre-charging system. I can grab a resistor if I need it. Once the system is on how many people ever use that pre-charge button again?

Movable wall-mount and rack mount ears would be nice, but for a "Budget" version I'd be OK losing those and building my own bracket.

Really, if there were a "Budget" model that just WORKED with none of the fancy stuff, I think that would be a great seller. You'd have to have a BMS that was simple enough you never had to go in and tweak it or reboot it or anything.

A low-temp cutoff is pretty important, but I wonder if having it as an "Optional Accessory" would be enough cost savings to make it viable or not. Most people aren't worried about their rackmount batteries being in freezing environments. Still needs to be some way of including it though.

Trying to bring it back to the original intent, ya know, Budget. :p
 
I'm actually happy with the budget model, the way it is. It's basically plug and play. And I can build my own mounting system. It's easy to get carried away with possible features. But, the main feature is affordability.
 
Looking at this list and I think the "Budget" part has flown out the window. :)

If I were looking for budget models, I think I'd start with "What do others have that I can lose?" and go from there.

I think the first thing I would give up is all the communications ports. If the battery turns on and provides power that's all I'd need. Maybe a BT module as those a re really cheap but again, all I really need is it to power on and provide power.

After that would be any kind of anti-theft (**COUGHCOUGHJAKPIERCOUGHCOUGH*) or position monitoring system. Actually, might start with that.

The next thing I'd lose would be any kind of pre-charging system. I can grab a resistor if I need it. Once the system is on how many people ever use that pre-charge button again?

Movable wall-mount and rack mount ears would be nice, but for a "Budget" version I'd be OK losing those and building my own bracket.

Really, if there were a "Budget" model that just WORKED with none of the fancy stuff, I think that would be a great seller. You'd have to have a BMS that was simple enough you never had to go in and tweak it or reboot it or anything.

A low-temp cutoff is pretty important, but I wonder if having it as an "Optional Accessory" would be enough cost savings to make it viable or not. Most people aren't worried about their rackmount batteries being in freezing environments. Still needs to be some way of including it though.

Trying to bring it back to the original intent, ya know, Budget. :p
With 48V especially, a built in precharge is essential. EVERY time the battery is switched off for any reason, the setup can surge and destroy or seriously weaken the inverter, or the BMS, or both. Turning it back on, stresses the entire system.

I agree, we can all install our own resistor and we can all be cautious and use it ourselves… heck, we are in the DIY solar forum after all… but if the battery didn’t come with it, the battery manufacturers can’t warranty as well and warranty is a big part of the price on these.
 
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With 48V especially, a built in precharge is essential. EVERY time the battery is switched off for any reason, the setup can surge and destroy or seriously weaken the inverter, or the BMS, or both. Turning it back on, stresses the entire system.
Glad you made that point. Thanks. :)
 
It makes sense, high voltage, combines with capacitor banks with RAPID discharge rates.
 
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