Why are people afraid of High Voltage Batteries?

[billvon]

Looks like a fury convention.

There's one of those at Burning Man every year.

 

[billvon]

400 dc volt you do not feel it , but kill the red cells .

Who told you that?

You absolutely feel it - and it's much worse than AC. Yes, it can kill red blood cells along with the rest of you. Our electrician has gotten hit (peripherally) with both 400VDC and 480VAC, and from his perspective, DC was much, much worse.

 

[MajicDiver]

Yet they turn around and do exactly the same thing with their batteries........

We are off grid and using 79.2 kWh of high voltage batteries (72 kWh usable). I wouldn’t have it any other way.

 

[OzSolar]

Here's the one I built a few years ago. A bunch of the locals dropped by for a picnic.
View attachment 221605

You can thank me later. Side note: this is a ridiculous thread. Any voltage above ~50v, regardless of AC or DC is dangerous. Continuing on that theme, any voltage above 400v is at least 8X's more dangerous than 50v. (you see where I'm going) IMHO there's no need to even discuss the finer points of AC vs DC when it comes to danger levels.

 

[Suijkerbuijk]

Who told you that?

You absolutely feel it - and it's much worse than AC. Yes, it can kill red blood cells along with the rest of you. Our electrician has gotten hit (peripherally) with both 400VDC and 480VAC, and from his perspective, DC was much, much worse.

The company i got my license from.
Wel the license have to replace on the 5 years.
My old license is from 2014
And have to be done by the company you work for.
I stop with this work reason my sickness.

I think you have to feel it to know it.
But not all cars run on 400/600 dc volts.
Hybride cars can be less of volts.

 

[jpwhit]

Well, I guess this thread has confirmed what I expected. Based on likes and positive posts, vs negative. Seems like it's about 50/50 in terms of people that understand HV batteries aren't that different than HV PV and HV AC.

And yet for the half of people that do seem to be afraid of HV batteries, but at the same time not HV AC or PV, I haven't seen a convincing argument for why they think it different.

It's interesting that some folks think HV batteries need more safety systems built into the technology before it's acceptable to adopt, while at the same time they have a 240V AC power panel in the house that'll kill you just as easily if you don't follow the appropriate safety precautions. HV DC batteries should be treated exactly the same way. Follow the appropriate safety precautions, engineer the system appropriately, and it'll serve its purpose well. I guess it's just that case that people will be afraid of what they don't understand.

 

[HowlerMonkey]

Any here work with HV batteries for a living?
I don’t consider myself a master at them but i’ve been diagnosing and replacing them since 2001 and have never been hit.

 

[Suijkerbuijk]

Well, I guess this thread has confirmed what I expected. Based on likes and positive posts, vs negative. Seems like it's about 50/50 in terms of people that understand HV batteries aren't that different than HV PV and HV AC.

And yet for the half of people that do seem to be afraid of HV batteries, but at the same time not HV AC or PV, I haven't seen a convincing argument for why they think it different.

It's interesting that some folks think HV batteries need more safety systems built into the technology before it's acceptable to adopt, while at the same time they have a 240V AC power panel in the house that'll kill you just as easily if you don't follow the appropriate safety precautions. HV DC batteries should be treated exactly the same way. Follow the appropriate safety precautions, engineer the system appropriately, and it'll serve its purpose well. I guess it's just that case that people will be afraid of what they don't understand.

No i do not think that is the problem.
I thinkt that people are use to use ac .
And grow op with is .
And not forget today systeem for ac are real good.
In my country you can take a power line in you bad and the systeem shutdown full for you are dead.

Well for dc its always tolt it can not harm you .
If you grap the poles of a battery .
And now people see an hear and learn to know that dc can kill you .
For the rest dc high voltage is new so still new home stuff are beult and make today.
Same with safety systeem for dc that new thinks come on the market
Like a dc high voltage breaker up to 1000volt .
That something new for home use.

I think over 20 years things will be more accept to use .

 

[1201]

Well, I guess this thread has confirmed what I expected. Based on likes and positive posts, vs negative. Seems like it's about 50/50 in terms of people that understand HV batteries aren't that different than HV PV and HV AC.

And yet for the half of people that do seem to be afraid of HV batteries, but at the same time not HV AC or PV, I haven't seen a convincing argument for why they think it different.

It's interesting that some folks think HV batteries need more safety systems built into the technology before it's acceptable to adopt, while at the same time they have a 240V AC power panel in the house that'll kill you just as easily if you don't follow the appropriate safety precautions. HV DC batteries should be treated exactly the same way. Follow the appropriate safety precautions, engineer the system appropriately, and it'll serve its purpose well. I guess it's just that case that people will be afraid of what they don't understand.

YOUR HV build includes custom BMS that you made. non available diy bms puts it out of reach of 99.9% of diyers. not everyone can custom design a bms solution like you.

 

[Mattb4]

Well, I guess this thread has confirmed what I expected...

That is either good or it is a case of Confirmation Bias. One has to be always careful that they do not pick and choose replies from others that serve to reinforce our expectations.

But anyone that agrees with me is not only right but a really smart person.

 

[jpwhit]

YOUR HV build includes custom BMS that you made. non available diy bms puts it out of reach of 99.9% of diyers. not everyone can custom design a bms solution like you.

You're right, the BMS configuration is less well understood in the DIY community currently, and there isn't as much readily available low-cost hardware available right off the shelf at the moment either. And if that's the reason someone is currently choosing to go with LV vs HV batteries at the moment, I completely agree that that makes sense.

My point is that I think the DIY community avoids HV battery systems because they think the HV DC is more dangerous than other dangerous voltages involved in DIY solar systems. And the reason I think that's not great, is because there is chicken and egg problem. If there is no interest in HV battery systems in the DIY community, then there is no demand to drive people to build and sell the kind of DIY components like BMS hardware to make it feasible for a wider portion of the DIY community.

I think the commercial battery market is will go to HV batteries fairly quickly. If the DIY community insists on staying with LV battery technology, then I think there will be fewer and fewer components available to them over time. And that not a recipe for a continued healthy DIY community.

As someone also already mentioned earlier in this thread. There is already, and it will continue to become more pronounced IMO, a glut of available salvage and surplus EV batteries. They are all HV batteries. It could become a bonanza of low cost very high quality source of ESS batteries for the EV community. Here's an example. 3 of the 4 modules in that pack were good. That's 60kwh of very high-quality batteries for $24 per KW. 90% of the BMS technology needed is already pre-wired with all the taps connected to cell groups. All that's needed to use that to complete the system is the right DIY compatible master BMS controller that could easily be made and sold for at most a few hundred dollars. This is just a Tesla example, same thing holds true for Ford, GM, Volvo, etc...

 

[MajicDiver]

I guess it's just that case that people will be afraid of what they don't understand.

It’s very wise to stay away from anything you don’t understand - until you have time to get an understanding of it. The key is an open mind, just because you don’t currently understand it does not mean there is no reason to try to get an understanding of it.

 

[1201]

You're right, the BMS configuration is less well understood in the DIY community currently, and there isn't as much readily available low-cost hardware available right off the shelf at the moment either. And if that's the reason someone is currently choosing to go with LV vs HV batteries at the moment, I completely agree that that makes sense.

My point is that I think the DIY community avoids HV battery systems because they think the HV DC is more dangerous than other dangerous voltages involved in DIY solar systems. And the reason I think that's not great, is because there is chicken and egg problem. If there is no interest in HV battery systems in the DIY community, then there is no demand to drive people to build and sell the kind of DIY components like BMS hardware to make it feasible for a wider portion of the DIY community.

I think the commercial battery market is will go to HV batteries fairly quickly. If the DIY community insists on staying with LV battery technology, then I think there will be fewer and fewer components available to them over time. And that not a recipe for a continued healthy DIY community.

As someone also already mentioned earlier in this thread. There is already, and it will continue to become more pronounced IMO, a glut of available salvage and surplus EV batteries. They are all HV batteries. It could become a bonanza of low cost very high quality source of ESS batteries for the EV community. Here's an example. 3 of the 4 modules in that pack were good. That's 60kwh of very high-quality batteries for $24 per KW. 90% of the BMS technology needed is already pre-wired with all the taps connected to cell groups. All that's needed to use that to complete the system is the right DIY compatible master BMS controller that could easily be made and sold for at most a few hundred dollars. This is just a Tesla example, same thing holds true for Ford, GM, Volvo, etc...

View attachment 221859

i would say most people are not afraid of HV. there is a lack of inverters, and the inverters available require very expensive batteries.

if we have affordable inverters and affordable diy hv bms the adoption rate will be much higher

 

[Suijkerbuijk]

i would say most people are not afraid of HV. there is a lack of inverters, and the inverters available require very expensive batteries.

if we have affordable inverters and affordable diy hv bms the adoption rate will be much higher

Wy need inverter?
I have 2 of them but are shutdown till i need them.

Almost all things i have use 12/24 volt power
The big 40" tv can run on 12 volt.
Fridge and freezer are in 12/24 volt models

Here is a link its in Dutch so use a translation to translate.
Its about how to use 12 volt in house.

Alles in huis op 12 Volt

Alles in huis op 12 Volt

www.12voltinhuis.nl

Alles in huis op 12 Volt

Installatie en verkoop van gelijkstroom systemen en apparatuur. Eén zonnepaneel gekoppeld aan een 12 Volt accu geeft voldoende stroom voor uw verlichting, tv en computer in uw huis. U heeft al 12 Volt in 1 dag!

www.12voltinhuis.nl

You can always use 12volt dc to 24 volt dc for other stuff that use about 19volt.
My phone chargers are 12volt DP charger for phone/tablet and laptop. ( Car model beult in)

You lose a lot of energy to go from 12/48 volt to ac 120/230 volt and after that go back to 19 volt tv that use it internal .

My inverter only use for cooking really
My wasmachine is camping model and have no heat systeem it do run on 230volt but only use 300watts . ( Use if i'm on holiday and away with the boat)
Just use a some hot water and drop it in from water cooker or from gas heating systeem in the wash machine.

Thare a lot of replacement for ac to dc on the market .

 

[Lt.Dan]

I would do HV batteries if the 48v server rack BMS's were available to be series connected. This makes it WAY more easy to make HV batteries with inherently less danger.

I should add to my original post, im personally not against HV batteries, I am stating that the reason it's not more mainstream is because there are way too many amateurs that think they know what they are doing. So companies dont want to come out with equipment that supports it, and then be liable for personal injury. Less than 50v is inherently safer to work with, and some guy can learn from yourube how to put it together.

 

[JRH]

I like staying with lower voltage gear( compared to many) because I don’t trust MY ability to operate mistake free…
I have made them in the past and I’m sure I will again…
Finally , I wish not be be on WSOC nightly news as they describe what happened to me.!!
…

 

[billvon]

Any here work with HV batteries for a living?
I don’t consider myself a master at them but i’ve been diagnosing and replacing them since 2001 and have never been hit.

I do. We repurpose EV batteries for use in BESS systems. Safety is a big issue. No one in our company has ever gotten a serious shock, but some have gotten minor ones (mostly 120VAC.)

 

[OzSolar]

Keeping in mind I'm an electrician that dabbles in off grid solar (not an EE) I would offer that 100 amps is my generic rule of thumb when it comes to voltage.

EG: When I designing something that is going to regularly go past 100 amps it's time to use a higher voltage battery. 48v is the cut off of readily available equipment to me otherwise I'd gladly use a HV battery.

If I'm doing the math right, a10kW inverter with 400VDC input could use #10 wire. That would be pretty cool!

 

[MajicDiver]

If I'm doing the math right, a10kW inverter with 400VDC input could use #10 wire. That would be pretty cool!

Exactly, that’s one reason I’m using the inverters and batteries I’m using. Also, in some situations it can be a big advantage to have batteries a long ways from the inverters, with HV batteries that’s no big deal at all.

 

[Supervstech]

Wy need inverter?
I have 2 of them but are shutdown till i need them.

Almost all things i have use 12/24 volt power
The big 40" tv can run on 12 volt.
Fridge and freezer are in 12/24 volt models

Here is a link its in Dutch so use a translation to translate.
Its about how to use 12 volt in house.

Alles in huis op 12 Volt

Alles in huis op 12 Volt

www.12voltinhuis.nl

Alles in huis op 12 Volt

Installatie en verkoop van gelijkstroom systemen en apparatuur. Eén zonnepaneel gekoppeld aan een 12 Volt accu geeft voldoende stroom voor uw verlichting, tv en computer in uw huis. U heeft al 12 Volt in 1 dag!

www.12voltinhuis.nl

You can always use 12volt dc to 24 volt dc for other stuff that use about 19volt.
My phone chargers are 12volt DP charger for phone/tablet and laptop. ( Car model beult in)

You lose a lot of energy to go from 12/48 volt to ac 120/230 volt and after that go back to 19 volt tv that use it internal .

My inverter only use for cooking really
My wasmachine is camping model and have no heat systeem it do run on 230volt but only use 300watts . ( Use if i'm on holiday and away with the boat)
Just use a some hot water and drop it in from water cooker or from gas heating systeem in the wash machine.

Thare a lot of replacement for ac to dc on the market .

The thread is about HIGH VOLTAGE and reasons why to fear it...

Not how to use low voltage for random reasons...

Please stay on topic.

 

[Supervstech]

I like staying with lower voltage gear( compared to many) because I don’t trust MY ability to operate mistake free…
I have made them in the past and I’m sure I will again…
Finally , I wish not be be on WSOC nightly news as they describe what happened to me.!!
…

Hey! A fellow charlotte area member!

And, yes, i have been featured on WSOC news reports for disasters...

Car crashes into home in south Charlotte

One south Charlotte apartment complex is without power Saturday night after a car crashed into a home in the complex.

www.wsoctv.com

Im the guy carrying the plywood...
And followed as a reputable HVAC tech... (back in the 80s)

 

[Suijkerbuijk]

The thread is about HIGH VOLTAGE and reasons why to fear it...

Not how to use low voltage for random reasons...

Please stay on topic.

In the topic are more people who replay on it to stay on low volt
I only tell that you do not need high volt its a option.
And yes high volt speciaal if you go up to 120/230 voor dc is more easy to set to ac 120/230volt.
This is how Solar panels work if it go to a grid network.
But that is not something you gone beult your self easy on a diy project
Reason is al ready tolt about it .
Its dangerous to do on diy .
And not even tolt about you insurance that will not pay out of it go wrong .
And even if it go wrong it means real wrong.
So its a good thing to tel that are other options to use.

That is a reason i have told this that are other options.
Its a forum to talk about it or not ?

 

[Hedges]

I would do HV batteries if the 48v server rack BMS's were available to be series connected. This makes it WAY more easy to make HV batteries with inherently less danger.

I think they can be. Just need a reverse-biased diode across the server rack battery, able to carry full current.
That way if any given server rack disconnects it BMS, it does not experience over-voltage.

But need to be careful about what isolation voltage it supports. To data comm (often opto-isolators good for a few hundreds volts and tested at thousands.) But also EMI filter capacitors to ground may also impose a limit; those often have to be removed to perform high voltage isolation testing.

i would say most people are not afraid of HV. there is a lack of inverters, and the inverters available require very expensive batteries.

if we have affordable inverters and affordable diy hv bms the adoption rate will be much higher

Some inverters out there including StorEdge and Sunny Boy Storage, they take an LG battery that is 150V with bidirectional DC/DC to 400V (causes some issues), or native 400V BYD.

Those batteries cost at least 2x what server rack do.
What we need is simply to know which BMS the inverters will work with.

But the inverters (at least SBS, which I have) support various firmware update versions depending on which battery, e.g. I can only update to a certain version using LG RESU-10H; later firmware isn't backwards compatible.

 

[Lt.Dan]

I think they can be. Just need a reverse-biased diode across the server rack battery, able to carry full current.
That way if any given server rack disconnects it BMS, it does not experience over-voltage.

But need to be careful about what isolation voltage it supports. To data comm (often opto-isolators good for a few hundreds volts and tested at thousands.) But also EMI filter capacitors to ground may also impose a limit; those often have to be removed to perform high voltage isolation testing.

I don't know enough about electronics/MOSFETs and other parts to understand why. But I've just been told that the MOSFETs are typically only rated to 60v, so series connecting them makes them prone to failure very quickly.

I will say, it would be awesome to be able to just series connected a 6x Rack of Server Rack batteries, to make a 307.2v nominal Battery to connect to a SolArk 30k or 60k. Easy peasy.

Who's gonna try it first???

 

[JRH]

Hey! A fellow charlotte area member!

And, yes, i have been featured on WSOC news reports for disasters...

Car crashes into home in south Charlotte

One south Charlotte apartment complex is without power Saturday night after a car crashed into a home in the complex.

www.wsoctv.com

Im the guy carrying the plywood...
And followed as a reputable HVAC tech... (back in the 80s)

They can make the simplest event so over dramatized with sour face and shocked expressions…
Ohhh the humanity…!
I’m up the mountain aways but they will send that chopper up here if bear pees in the highway and they hear about it..