Nissan Leaf battery for offgrid storage

[SunEagle]

Please guys, can we focus on how to use these EV batteries on solar systems?

Thank you.

My guess is that unless you can get the output voltage of your charger to be in the range to charge that EV battery, using solar will be a hard climb to make. That is one of the reasons the Tesla battery is very specific to the solar inverter/charger that they match up with.

I seriously doubt you could use something from SMA or Midnite CC to charge a Powerwall system so you might have the same issue with that Leaf battery. You might need some type of Auto-transformer to provide the correct voltage for the EV battery.

[Sunking]

I seriously doubt you could use something from SMA or Midnite CC to charge a Powerwall system so you might have the same issue with that Leaf battery. You might need some type of Auto-transformer to provide the correct voltage for the EV battery.

You are exactly right SE. Most consumers think Lithium batteries are of all foolish things are Lithium batteries. They have no clue there are over a dozen different types (chemistries) and each has it own unique charging characteristics and voltages. There is only one type that is compatible with Pb batteries. If you do not know what that types is I am not going to say. If you do not know then you have no biz fooling with any battery. What I will say there is no EV made that uses them. At least no EV manufacture you would want to buy from unless you are a Chi-Com. In a nut shell all EV battery cell voltages are too high and not compatible with most solar charge controllers. The one or two I know of are too small to be of much real use.

Here is a tidbit I will give. Tesla vehicles and Powerwall use the most dangerous Lithium Ion battery. The type you here about on the news with all the fires. It also has the shortest cycle life of 300 to 500 cycles. It has to do with the Energy Density, the type used is the highest energy density which makes it unstable and why Tesla gets the range no other EV can.

[vast]

SunEagle,
I already have a Midnite Classic 150 as solar charger and I intend to buy an Victron inverter-charger.

[jflorey2]

Please guys, can we focus on how to use these EV batteries on solar systems?
Thank you.

Sounds like a great idea. Used EV batteries must be cheap, right? There are several problems that stand in your way.

1) EV companies don't want you to do this. They have enough liability problems due to flammability of the battery; the last thing they need is some guy using a homemade BMS and burning his house down. The news, of course, would report "Nissan battery burns house down." So they don't make it easy; EV batteries need to be "spoofed" via the CAN bus to turn on at all, and this isn't easy to do.

2) Even if you do spoof it and get it to turn on, it's going to be a 200 to 600 volt battery. (Leaf batteries are 400 volts.) Most hybrid inverters need 48 volts or a similar voltage. You'd need a StorEdge or similar to use a 400 volt battery (and they're not listed as compatible with Leaf batteries so you are endangering the warranty.)

3) So you got one but you have a 48 volt inverter - so you decide to rebuild the battery to support this. This is a lot of work and you need to add your own BMS. BMSes quite often do more harm than good and will tend to unbalance/discharge packs unless you know exactly what you are doing. The cost of failure is a dead battery (at best) or a fire (at worst.) If you are going to do this you are far better off buying CALB cells or some other similar LiFePO4 batteries; their prices are similar to used EV batteries. No BMS of course.

4) Used EV batteries often have problems. The 2011-2012 Leaf batteries, for example, died very rapidly when used at high temperatures (i.e. Phoenix, Los Angeles.) And a lot of them were used there. So if you see an amazing price on a Leaf battery, it's probably a 2011-2012 battery from Phoenix, and you'll end up with a high ESR 10kwhr battery.

All that being said, there are some good ways to use EV batteries in a home system

1) Buy a product that integrates EV batteries for home use. Mercedes-Benz used to sell one; you may still be able to find them on line.

2) Buy an EV and use a timer to charge your EV when the sun is out. Or get fancier and get some logic that charges at X kilowatts only when solar production is greater than X kilowatts. Gives you 'free' charging via your solar system. And of course if your power goes out you can run an inverter off the 12V system in the car to get a little power for lights and cellphones and whatnot.

3) Buy a V2G system and use the EV's battery directly via the ChaDeMo or DCFC connector. These exist but are VERY expensive, and are considered experimental, so it will be very hard to get one. They contain their own inverters as well. When you use one of these, you are taking advantage of all the EV's battery protection, balancing and charge management features, so the odds of grief are low.

[SunEagle]

SunEagle,
I already have a Midnite Classic 150 as solar charger and I intend to buy an Victron inverter-charger.

I think you will still need some type of transformer that converts the charger output voltage to the correct battery charging voltage. Even Tesla used an Auto-transformer in one of their designs to charge the Powerwall from solar panels. You might also need that transformer for a Leaf or any other EV battery.

[Murby]

Sounds like a great idea. Used EV batteries must be cheap, right? There are several problems that stand in your way.

1) EV companies don't want you to do this. They have enough liability problems due to flammability of the battery; the last thing they need is some guy using a homemade BMS and burning his house down. The news, of course, would report "Nissan battery burns house down." So they don't make it easy; EV batteries need to be "spoofed" via the CAN bus to turn on at all, and this isn't easy to do.

And of course, to my knowledge, absolutely no one "spoofs" the manufactures battery controller.. At least I've never heard of anyone doing that for the purpose of solar storage.

Also to my knowledge, no house has ever burned down or fire ever been reported due to an EV battery being used for solar storage. I'm not saying it hasn't happened, I'm saying I already looked into it and couldn't find a single incident.

Furthermore, most of the Lithium Ion batteries that have caught fire were due to either manufacturing defects, which are caught fairly quickly, or the owners trying to fast charge the batteries like they do in the vaporizer gizmos. Lithium batteries tend to grow something called a "dendrite" between the cathode and the anode.. The dendrites in lithium batteries are like a stalagmites in caves and from what I understand, charging a battery too quickly causes them to grow really quickly.. when they make contact and connect the anode or cathode, a fire can result.

I'm sure there have been other fires caused by other issues (physical damage, abuse, etc), but again, not a single EV battery being used for solar storage that I could find.

I did find a video on Youtube of someone trying to set a Leaf battery pouch on fire.. best they could do is get a puff of smoke out of it when they repeatedly stabbed it with a screw driver.

Perhaps you can provide a link to these solar battery fires?

Besides, what silly person would put any large dangerous battery, (Lithium or Lead Acid) inside their home? That's just crazy.. There's an invention called "A box".. you can even build one yourself and put it outdoors.. worst case scenario is your box catches on fire if its built out of wood. Build it out of steel and the issue is solved.

2) Even if you do spoof it and get it to turn on, it's going to be a 200 to 600 volt battery. (Leaf batteries are 400 volts.) Most hybrid inverters need 48 volts or a similar voltage. You'd need a StorEdge or similar to use a 400 volt battery (and they're not listed as compatible with Leaf batteries so you are endangering the warranty.)

And why would anyone do such a thing??

3) So you got one but you have a 48 volt inverter - so you decide to rebuild the battery to support this. This is a lot of work and you need to add your own BMS.

Actually, its not that much work at all. From what I've seen from the mini-documentaries on youtube, these guys are able to tear these batteries apart and reconfigure them in a very short time.
The EV batteries I've seen most of, the leaf and volt, are just a bunch of individual packs.. heck, they almost look like Filter Press plates when they're stacked together. For the leaf battery, they just purchase some copper flat bars, drill the appropriate holes, and they're basically done. All these EV battery modules seem to come with conveniently accessible lug terminals.

[quote]
BMSes quite often do more harm than good and will tend to unbalance/discharge packs unless you know exactly what you are doing. The cost of failure is a dead battery (at best) or a fire (at worst.) If you are going to do this you are far better off buying CALB cells or some other similar LiFePO4 batteries; their prices are similar to used EV batteries. No BMS of course. [quote]
I researched this "BMS does more harm than good" statement after the last person said it, and I couldn't find one link to back this up.. The purpose of a BMS is to prevent unbalanced packs and to protect the battery and you're claiming it does the opposite.

Do you, by any chance, use lithium ion batteries to build toys also???? I only ask because every time I see doom and gloom statements that make use of fear mongering that can't be substantiated by other sources, it usually means someone isn't being... umm.. lets say "accurate".

Can a BMS fail and cause a fire? Sure, I believe that to be true.. but if you purchase a cheap tire and put it on your car to race down the road at 80mph, it too can cause death and destruction.

4) Used EV batteries often have problems. The 2011-2012 Leaf batteries, for example, died very rapidly when used at high temperatures (i.e. Phoenix, Los Angeles.) And a lot of them were used there. So if you see an amazing price on a Leaf battery, it's probably a 2011-2012 battery from Phoenix, and you'll end up with a high ESR 10kwhr battery.

I looked into this also and this happens to be accurate and truthful.. and good advice.

My research is showing me that the VOLT batteries are far better than the Leaf batteries.. and from what I'm reading its because the Leaf battery is passively cooled whereas the VOLT battery has liquid cooling. If you find a leaf battery from the northern latitudes, you'll probably be fine.. problem is verification.

There are claims (more than one or two) of Chevy Volts going 200,000 miles with almost no battery degradation.

All that being said, there are some good ways to use EV batteries in a home system

1) Buy a product that integrates EV batteries for home use. Mercedes-Benz used to sell one; you may still be able to find them on line.

2) Buy an EV and use a timer to charge your EV when the sun is out. Or get fancier and get some logic that charges at X kilowatts only when solar production is greater than X kilowatts. Gives you 'free' charging via your solar system. And of course if your power goes out you can run an inverter off the 12V system in the car to get a little power for lights and cellphones and whatnot.

3) Buy a V2G system and use the EV's battery directly via the ChaDeMo or DCFC connector. These exist but are VERY expensive, and are considered experimental, so it will be very hard to get one. They contain their own inverters as well. When you use one of these, you are taking advantage of all the EV's battery protection, balancing and charge management features, so the odds of grief are low.

Or just buy a good used EV battery, reconfigure it, slap on a quality BMS system (not some Chinese piece of junk), and save a bunch of money.

I've been doing loads and loads of research on the EV batteries being used in other applications, especially solar.. Been trying really hard to verify the "doom and gloom" claims made by several members in this forum... and I'm not finding these claims to be accurate.

What I am seeing are a bunch of unfair and unrealistic comparisons (comparing $2K Lithium battery to a $6K lead acid) worst case scenarios, lack of suggested solutions, and fear mongering on a level comparable to the biblical nut jobs who think the world is going to end.

And I haven't given up.. I'm still trying to verify and substantiate the discouraging claims being made by a few members here.... I just haven't been able to.

[SunEagle]

[QUOTE=Murby;n378983]
And of course, to my knowledge, absolutely no one "spoofs" the manufactures battery controller.. At least I've never heard of anyone doing that for the purpose of solar storage.

Also to my knowledge, no house has ever burned down or fire ever been reported due to an EV battery being used for solar storage. I'm not saying it hasn't happened, I'm saying I already looked into it and couldn't find a single incident.

Furthermore, most of the Lithium Ion batteries that have caught fire were due to either manufacturing defects, which are caught fairly quickly, or the owners trying to fast charge the batteries like they do in the vaporizer gizmos. Lithium batteries tend to grow something called a "dendrite" between the cathode and the anode.. The dendrites in lithium batteries are like a stalagmites in caves and from what I understand, charging a battery too quickly causes them to grow really quickly.. when they make contact and connect the anode or cathode, a fire can result.

I'm sure there have been other fires caused by other issues (physical damage, abuse, etc), but again, not a single EV battery being used for solar storage that I could find.

I did find a video on Youtube of someone trying to set a Leaf battery pouch on fire.. best they could do is get a puff of smoke out of it when they repeatedly stabbed it with a screw driver.

Perhaps you can provide a link to these solar battery fires?

Besides, what silly person would put any large dangerous battery, (Lithium or Lead Acid) inside their home? That's just crazy.. There's an invention called "A box".. you can even build one yourself and put it outdoors.. worst case scenario is your box catches on fire if its built out of wood. Build it out of steel and the issue is solved.


And why would anyone do such a thing??


Actually, its not that much work at all. From what I've seen from the mini-documentaries on youtube, these guys are able to tear these batteries apart and reconfigure them in a very short time.
The EV batteries I've seen most of, the leaf and volt, are just a bunch of individual packs.. heck, they almost look like Filter Press plates when they're stacked together. For the leaf battery, they just purchase some copper flat bars, drill the appropriate holes, and they're basically done. All these EV battery modules seem to come with conveniently accessible lug terminals.

[quote]
BMSes quite often do more harm than good and will tend to unbalance/discharge packs unless you know exactly what you are doing. The cost of failure is a dead battery (at best) or a fire (at worst.) If you are going to do this you are far better off buying CALB cells or some other similar LiFePO4 batteries; their prices are similar to used EV batteries. No BMS of course.

I researched this "BMS does more harm than good" statement after the last person said it, and I couldn't find one link to back this up.. The purpose of a BMS is to prevent unbalanced packs and to protect the battery and you're claiming it does the opposite.

Do you, by any chance, use lithium ion batteries to build toys also???? I only ask because every time I see doom and gloom statements that make use of fear mongering that can't be substantiated by other sources, it usually means someone isn't being... umm.. lets say "accurate".

Can a BMS fail and cause a fire? Sure, I believe that to be true.. but if you purchase a cheap tire and put it on your car to race down the road at 80mph, it too can cause death and destruction.


I looked into this also and this happens to be accurate and truthful.. and good advice.

My research is showing me that the VOLT batteries are far better than the Leaf batteries.. and from what I'm reading its because the Leaf battery is passively cooled whereas the VOLT battery has liquid cooling. If you find a leaf battery from the northern latitudes, you'll probably be fine.. problem is verification.

There are claims (more than one or two) of Chevy Volts going 200,000 miles with almost no battery degradation.


Or just buy a good used EV battery, reconfigure it, slap on a quality BMS system (not some Chinese piece of junk), and save a bunch of money.

I've been doing loads and loads of research on the EV batteries being used in other applications, especially solar.. Been trying really hard to verify the "doom and gloom" claims made by several members in this forum... and I'm not finding these claims to be accurate.

What I am seeing are a bunch of unfair and unrealistic comparisons (comparing $2K Lithium battery to a $6K lead acid) worst case scenarios, lack of suggested solutions, and fear mongering on a level comparable to the biblical nut jobs who think the world is going to end.

And I haven't given up.. I'm still trying to verify and substantiate the discouraging claims being made by a few members here.... I just haven't been able to.

Murby

Since you do not believe what we are trying to tell you then go do what you want and just shut the F up.

[Murby]

Murby

Since you do not believe what we are trying to tell you then go do what you want and just shut the F up.

Translation: We use these batteries for fun and there's a limited supply of them.. so to that end, we are attempting to discourage people by scaring them away from pursuing these projects so that our limited supply doesn't become more limited.

Once again, I have no beliefs.. I operate using facts and evidence, and the facts and evidence do not support the doom and gloom statements. In fact, they say the opposite.

If what you folks are claiming is true, why not post links backing up the claims?

If you're going to mislead people for personal profit, you shouldn't get mad when someone calls you out on it.

[SunEagle]

Translation: We use these batteries for fun and there's a limited supply of them.. so to that end, we are attempting to discourage people by scaring them away from pursuing these projects so that our limited supply doesn't become more limited.

Once again, I have no beliefs.. I operate using facts and evidence, and the facts and evidence do not support the doom and gloom statements. In fact, they say the opposite.

If what you folks are claiming is true, why not post links backing up the claims?

If you're going to mislead people for personal profit, you shouldn't get mad when someone calls you out on it.

I don't make a dime telling people what to do concerning solar and as far as I know no one else here gets paid or sells anything to the members on this forum.

If you want to protect your stash of EV batteries then go ahead but I have doubts about your level of thinking considering you claim to be a preper which IMO has a mind out where the buses don't run. I would suggest you not fear the shadows or conspiracy theories because it can mess up your life.

Again if you don't like what we are saying and truly believe we are out to steal your batteries then so be it but please go somewhere else and post your ideas.

[Murby]

I don't make a dime telling people what to do concerning solar and as far as I know no one else here gets paid or sells anything to the members on this forum.

I never claimed or implied you made money in this forum, but if I posted something that you believe does, please quote it and I'll explain myself or apologize if I made such an accusation.

If you want to protect your stash of EV batteries then go ahead but I have doubts about your level of thinking considering you claim to be a preper which IMO has a mind out where the buses don't run. I would suggest you not fear the shadows or conspiracy theories because it can mess up your life.

LOL.. When you say that, I get a picture of some Kentucky redneck digging underground bunkers because he thinks the government is evil.. I can assure you I am not one of them, but I don't take offense to your comment because I understand how certain television shows give people that idea.

When hurricane Katrina struck, I bet there were a lot of people wishing they had prepared for such a disaster.. You'd think the folks in Puerto Rico would have learned from Katrina, but nope.

When the Eastern US electrical grid went down in 2003, I watched Detroit turn into a mini war zone.. (although in truth, its not much better even with the power on) I had neighbors who's homes were about to flood because they couldn't run their sump pumps. And that was just five days.

So you're not a prepper eh? You don't take any actions to minimize the effects of disaster in your life? No insurance on your home? I bet your Grandmother was a prepper, I bet she canned food and put it in the basement, stashed money away, kept matches and candles, etc. Was your Grandmother out of her mind too?

If you're not prepping for a disaster, why have insurance on your home? The biggest difference is that when you pay your insurance premiums, you never see your money again. You purchase shampoo for the next month, I purchase it for the next three years.

And I certainly don't buy into conspiracy theories.

Again if you don't like what we are saying and truly believe we are out to steal your batteries then so be it but please go somewhere else and post your ideas.

I'm here sharing and gathering information like everyone else. And like everyone else, I'm working to weed out the facts from any bad advice, misinformation, or inaccurate statements. I'm doing research, and when someone tells me something, I look up the information to learn more about what they are telling me.

Imagine my surprise when I find that rather knowledgeable person(s) are making statements that don't seem to be substantiated by other sources.. So I ask for links from you folks to back up the claims and have yet to see any.. Not a one.. Instead, I get hostility and anger and am told to go away.

I've learned a lot from this forum, it was incredibly helpful when I was doing research on my own solar array. Time permitting, I think I owe it to other members to be just as helpful to them.

[Sunking]

And of course, to my knowledge, absolutely no one "spoofs" the manufactures battery controller.. At least I've never heard of anyone doing that for the purpose of solar storage.

Are you really that ignorant? DIY EV guys have been trying for years to crack Telsla battery modules and have not done it. The DIY EV guys know a heck of a lot more than any solar weeinie wannabe, and many are engineers and technicians.

Besides, what silly person would put any large dangerous battery, (Lithium or Lead Acid) inside their home? That's just crazy.. There's an invention called "A box".. you can even build one yourself and put it outdoors.. worst case scenario is your box catches on fire if its built out of wood. Build it out of steel and the issue is solved.

This proves just how misinformed and ignorant you really are.

Just about every off-grider keeps their batteries inside their living space. Every telephone office and many are located in commercial public high rise buildings with huge 48 volt 20,000 to 50,000 AH batteries occupying several thousand square feet of floor space. Every data center, every cell tower site, banks, department stores, and dozens of other applications have giant size3d battery banks indoor.

[jflorey2]

Also to my knowledge, no house has ever burned down or fire ever been reported due to an EV battery being used for solar storage. I'm not saying it hasn't happened, I'm saying I already looked into it and couldn't find a single incident.

There was a recent incident reported on EndlessSphere (EV bike forum) where someone used a repurposed battery pack for their ebike. It caught on fire and burned their garage down. He was VERY fortunate that the fire department put it out before it spread to his house.

And you've probably heard about the 787 lithium battery fires. That was with a battery built to a much higher standard.

I did find a video on Youtube of someone trying to set a Leaf battery pouch on fire.. best they could do is get a puff of smoke out of it when they repeatedly stabbed it with a screw driver.

I've done quite a bit of testing with 18650 and pouch cells for cellphones. Nail punctures had about a 50/50 chance of causing a fire. All outgassed like crazy. These were all LiCo cells (same sort you see in the Powerwall and in Teslas.)

Besides, what silly person would put any large dangerous battery, (Lithium or Lead Acid) inside their home? That's just crazy.

You are calling most off gridders (and users of the Powerwall) crazy - while at the same time claiming you are superior to them. That's not really a formula for success.

There's an invention called "A box".. you can even build one yourself and put it outdoors.. worst case scenario is your box catches on fire if its built out of wood. Build it out of steel and the issue is solved.

Yep. And there is another thing called "experience." You may have never heard of it, but it's pretty useful. You can even get some yourself, if your ego lets you.

Actually, its not that much work at all. From what I've seen from the mini-documentaries on youtube, these guys are able to tear these batteries apart and reconfigure them in a very short time.

Yep, And I saw a Youtube video of a guy who built a steam rocket and launched himself a thousand feet in the air. Didn't take him that long according to the video. If he can do it, it must be pretty easy and safe.

Do you, by any chance, use lithium ion batteries to build toys also????

Nope. Other people do - people with years of experience designing and testing lithium ion packs. I did it for phones rather than toys. The entire process, from start of design to first phone sold, was about 24 months.

Can a BMS fail and cause a fire? Sure, I believe that to be true.. but if you purchase a cheap tire and put it on your car to race down the road at 80mph, it too can cause death and destruction.

Excellent point. And if you have never driven in your life, and you see a Youtube video on how to race, and so you go buy a car and race down the road at 80mph because "it looked pretty safe on the Youtube video" it can also cause death and destruction. Might be better to start in a parking lot driving slowly, then take a driver's ed course, then get a license, then get some experience driving, then go to some advanced driver training - and THEN try that race. That is slow and boring, and it's what all those evil race car drivers tell you to do (because they don't want to share the track with you because they are greedy) but might be a good idea.

Or just buy a good used EV battery, reconfigure it, slap on a quality BMS system (not some Chinese piece of junk), and save a bunch of money.

Yep. Just get something cheap, slap something on and save a bunch of money! One, two, three, done, without all that experience and testing that those stupid battery system manufacturers say is required. I can't believe more people don't do this!

I've been doing loads and loads of research on the EV batteries being used in other applications, especially solar.. Been trying really hard to verify the "doom and gloom" claims made by several members in this forum... and I'm not finding these claims to be accurate.

Feel free to learn the hard way. Just don't take anyone else with you.

I hope your experience bucket fills up before your luck bucket runs out, but with your ego that might be unlikely.

[Murby]

Are you really that ignorant? DIY EV guys have been trying for years to crack Telsla battery modules and have not done it. The DIY EV guys know a heck of a lot more than any solar weeinie wannabe, and many are engineers and technicians.

And eggs are yellow and white inside! What does your reply have to do with my statement? This isn't the DIY EV forum or thread, we're talking about solar storage batteries. Are you suggesting that DIY solar storage folks are hard at work trying to crack Tesla's battery modules? Or are you just arguing for the sake of making up an argument?

Just about every off-grider keeps their batteries inside their living space.

There you go with that misinformation again...

http://forum.solar-electric.com/discussion/7424/where-do-you-have-your-battery-bank-located-why

Did you not think there would be a thread about this on the internet somewhere? Not difficult to find. Very few people put batteries inside their home or living space.. I know some folks will park their motorcycles inside their home next to a couch or something, but most people put them in the garage, a shed, a barn, or whatever. You'd have to be pretty foolish to put a large battery bank inside your home, and I'm not talking about a couple of 12 volt batteries so you can have lights, I'm talking about a 20kW storage system. Not only is it a lot of weight, its hydrogen gas, sulfuric acid, and a lot of problems.

Who do you think you're fooling with this nonsense? Or was "living space" some trick on words?

Every telephone office and many are located in commercial public high rise buildings with huge 48 volt 20,000 to 50,000 AH batteries occupying several thousand square feet of floor space. Every data center, every cell tower site, banks, department stores, and dozens of other applications have giant size3d battery banks indoor.

What the heck does that have to do with what we are talking about? Places like that also run fork trucks around, have a fire extinguisher every 50 or 75 feet, an exit door, and probably a sprinkler system the local fire department can plug into.. and in the case of a building housing batteries, its probably a specialized sprinkler system... do you run a fork truck around inside your home??

If we're going to go off into LaLa land with the irrelevant statements and subject matter, I'd prefer if we talk about something more interesting like maybe Stellar Nucleosynthesis.. Astrophysics is something I really enjoy spending my free time on. Anytime you want to have a discussion about the formation of a neutron star, a black hole, the hypothesized quark star, electron degeneracy, neutron degeneracy, the Pauli Exclusion Principle, or any other similar subject, I'm all for it. Or we can talk about Dark Matter.. maybe the relevance of Dragonfly 44 or perhaps DF2, or maybe.. maybe we can talk about something just as irrelevant as industrial battery storage, we can talk about the Lithium abundance problem after the big bang and/or how it affects our current models.

But in this thread, we're talking about Lithium Ion Batteries for solar storage, the claimed doom and gloom, and the total lack of supporting information and how its replaced with discouragement and bad information.. in fact, I dare call it "intentionally misleading and false information".

Anyone got a link to an expensive learning experience involving lithium solar storage batteries?

[Murby]

There was a recent incident reported on EndlessSphere (EV bike forum) where someone used a repurposed battery pack for their ebike. It caught on fire and burned their garage down. He was VERY fortunate that the fire department put it out before it spread to his house.

And you've probably heard about the 787 lithium battery fires. That was with a battery built to a much higher standard.

I've done quite a bit of testing with 18650 and pouch cells for cellphones. Nail punctures had about a 50/50 chance of causing a fire. All outgassed like crazy. These were all LiCo cells (same sort you see in the Powerwall and in Teslas.)

Which is why I would never put a large battery bank inside my home.

You are calling most off gridders (and users of the Powerwall) crazy - while at the same time claiming you are superior to them. That's not really a formula for success.

Care to quote where I claimed I was superior to them or anyone else? More false information?? We're just making stuff up now?
Pretty poor defense.

Putting a large energy storage device inside your home is not wise in my opinion.. If you think it is, then we can agree to disagree.

Yep. And there is another thing called "experience." You may have never heard of it, but it's pretty useful. You can even get some yourself, if your ego lets you.

Yep, And I saw a Youtube video of a guy who built a steam rocket and launched himself a thousand feet in the air. Didn't take him that long according to the video. If he can do it, it must be pretty easy and safe.

Nope. Other people do - people with years of experience designing and testing lithium ion packs. I did it for phones rather than toys. The entire process, from start of design to first phone sold, was about 24 months.

Excellent point. And if you have never driven in your life, and you see a Youtube video on how to race, and so you go buy a car and race down the road at 80mph because "it looked pretty safe on the Youtube video" it can also cause death and destruction. Might be better to start in a parking lot driving slowly, then take a driver's ed course, then get a license, then get some experience driving, then go to some advanced driver training - and THEN try that race. That is slow and boring, and it's what all those evil race car drivers tell you to do (because they don't want to share the track with you because they are greedy) but might be a good idea.

Yep. Just get something cheap, slap something on and save a bunch of money! One, two, three, done, without all that experience and testing that those stupid battery system manufacturers say is required. I can't believe more people don't do this!

Feel free to learn the hard way. Just don't take anyone else with you.

I hope your experience bucket fills up before your luck bucket runs out, but with your ego that might be unlikely.

I was going to reply to the individual statements but the entire thing is just basically sarcastic remarks being used in lieu of a rational defense of the subject matter.

But hey, if you can't defend a position, just attack and insult the other side.. I get it. Its an argument fallacy called "Ad Hominem"..

[nebster]

Murby,

There is definitely an element of doom and gloom in some cases, and overt conservatism in others. This forum in particular harbors some... interesting... posters with interesting perspectives. (It is also clear that very few actually are managing an at-scale ESS lithium pack themselves, for what that's worth.)

In general I feel like the safety record with cobalt chemistries is quite surprisingly good, considering how omnipresent they are, how infrequently we read about disasters, and yet how absolutely intimidating the stoichiometry is for them in the exothermic region.

Some of the comments about lifecycle seem too pessimistic to me. Don't drive the pack to >90% SOC, keep the temperatures reasonable, keep C < 0.5, and any modern lithium chemistry in an ESS setting is going to do way better than a thermally-unprotected Leaf battery in Nevada. I have ~100 cycles on my LFP pack and don't see any hint of degradation. I wish I had 1000 and could confirm my hypothesis, but that'll take a few years. There are a few documented passively-managed LFP packs in a few DIY EVs with very stable performance after 7 or 8 years, so that's promising, I think.

The BMS-kills-packs argument seems more legitimate: homebrew BMSes implemented poorly with current imbalance and crappy "balance boards" have nuked many a cell, and there are lots of documented packs that have then deteriorated way too quickly. In an ESS scenario a pure passive configuration makes more sense: cell level HVD, LVD, don't try to reach 100% SOC, don't get fancy, don't get greedy.

Definitely put the homebrew ESS pack away from the house. This is not an option for those of us using ESS in a mobile application, so most of us in this use case therefore choose to use LFP for thermal safety. (But some are using cobalt chemistries even in these settings, and they'll probably still be alive in ten years... the risk versus performance/cost trade-off has to be made on a personal level at that point.)

Cheers.