Tesla Battery charged to 28 volts, popping and shorted out

[SG-1]

If you are happy and content with that, that's all that counts.

Not having a go at you but I think the whole " No power bills" Idea is way overblown... Much like the EV proponents carry on abut not having to do oil changes like they need to be done every day and cost $500 a pop. If you can't afford 4 oil changes a year, sell the damn car and walk!

What I see in various places is people akin to people boasting they never have to pay for fuel at a petrol station because theybare running their car on Chanell No. 5. If the overall cost is greater, whats the freaking point?

My last power bill was $1.47 per day. That is grid connection charges and power I used. I have no batteries but a heap of panels.
I cannot make my own power independently for that. If I costed out all the equipment I'd have to buy and amortized the cost of the batteries, inverters, controllers wiring and components over their life and the ongoing costs of replacement when things failed, would not work out by a long shot.

You battery cost alone is nearly $1.20 a day over 10 years and you had to pay that up front lump sum. If you didn't pay cash, it cost you more. If you did there is lost interest or investment returns.
I think the idea of no power bills is the wrong and a rather naieve attitude.

The thing I look at is how do I get the power I need at the lowest possible Cost?

Not having a power bill to me is pointless if I'm paying more for power than I could otherwise. The object of the game to me is make my power cost as low as it can be. ATM, for me that's stay on the grid. That may change, even in the next 12 Months but the goal will still remain the same.
Others may have other goals and thats fine but if its not lowest cost power, they should not push that as a justification.

The other thing I hear a lot and equally do not understand is people spending large amounts of money on battery / solar systems for blackout protection. Often these outages are infrequent and short when they do happen. Spending thousands as is often the case for a dozen hours a year if that of outages when someone could just go buy a generator for a few hundred bucks and probably spend $10 on fuel also makes no sense to me and I put it down to just another internet mentality in a lot of cases. People doing what everyone else does because the want the approval and acceptance of others and to be accepted into the heard.

If people want to be independent, thats another thing but it's different to " No power bills" . I can be independent at a moments notice. Fire up the gennys and I can run for a week without leaving the place. If I needed to go longer I could with preparation ( store more oil) but I think the sum total of outages here in the last 3.5 Years I have been in this place have been about 8 Hours and that was mainly one incident. At my old house I think I had about 8 hours outage in about 20 Years. Most annoying as I never got to justify my toys to the Mrs near enough.

I am quite well off at this stage of life ( which probably means something bad will happen) but I had the arse out my pants for a long time and while I am a tight arse, I also don't see the point of spending more money than one has to for something unexciting and fundamental like Power. Maybe a dream holiday or get the Bike or car you want and will give you a lot of pleasure and ongoing enjoyment as well as have resale/ investment value, different thing but boring arse electricity?

It's clear to anyone not trying to fool themselves that a LOT of people here and elsewhere are completely kidding themselves thinking they are saving money with their panel and battery setups. It's pure and utter fantasy to think they are saving money. If they want to do it as a hobby, Fine, just admit that and don't try and say there is a benifit which there plainly is not. It is extremely difficult to go off grid cheaper than you can stay on grid if it is available. Even trying to save money on grid costs becomes a very difficult thing once batteries get involved.

Most people with that say ooh, look, I halved my power bill but ignore the money they already spent doing it which in the majority of cases they will never get back and their total power costsvare HIGHER than what they were without all the stuffing round.
I'm just glad these people aee not running my business, I'd be broke years ago.

With solar only, both my and my fathers power costs are far more for grid connection than the power we use. Panels have a hugely better payback on their own with grid tie than batteries do much as some find that fact not something they want to hear let alone admit.

That said, If it gives a person contentment and keeps them out of whore houses and gives them something to do other than shoot up, then their money, fair enough, we all need to fill in our spare time.
I think in general, these ideals that are in most cases flawed in the agenda they purport as their purpose and benifit, are well over extolled and pushed as a justification way too much.

I do not need your approval, or your support. I know what my plan is and how it's going to work. Sure TESLA power walls are NOT a worthwile investment, but for minimum 8k and not having to put 10kWh system on your roof just so the power company can give back 2-3 cents per kWh while still charging you maximum prices during peak times when you really need it. Live in your dream world I will look at reality and hope our children will have a world to inherit once people like yourself destroy it.

In saying that this thread was all about someone asking about there now dead Tesla Battery, so get back on topic . . .

 

[Gazoo]

The other thing I hear a lot and equally do not understand is people spending large amounts of money on battery / solar systems for blackout protection. Often these outages are infrequent and short when they do happen. Spending thousands as is often the case for a dozen hours a year if that of outages when someone could just go buy a generator for a few hundred bucks and probably spend $10 on fuel also makes no sense to me and I put it down to just another internet mentality in a lot of cases. People doing what everyone else does because the want the approval and acceptance of others and to be accepted into the heard.

I could have gotten by with a UPS for blackouts....maybe. The reason I chose to build my own UPS is because the run time of a readily available UPS like APC's and the like is very limited. And since I live in an apartment I can't use a generator or solar. I am not finished completing my project. I am taking my time but at least my pack is useable and I have a cheap inverter I can use until I decide on a good one in the event of a blackout. Also it's a hobby for me and presented several challenges which so far I have overcome and can always improve on. I didn't do this because everyone else is doing it or to be accepted into the heard. I did it because I wanted to. You do make valid points however and I understand those points.

I am glad I found this forum. I was considering Tesla modules before and am happy I didn't go that route because of the cost, but mainly because of the possible hazards, and went with LFE instead. I didn't realize how much LFE prices had come down. I didn't even know one could buy 280ah cells when I found this forum and have found much larger LFE cells with much more capacity that I never knew existed either.

 

[Hedges]

My last power bill was $1.47 per day. That is grid connection charges and power I used. I have no batteries but a heap of panels.

My electric bill is $0.33/day. PG&E with net metering provides power storage cheaper than batteries.
Gas bill is usually $0.25/day. More if I decide to heat with gas instead of electric.

For 15 years I had only PV panels, no batteries. Could never justify the cost.
I finally put in batteries and battery inverters like I always wanted to because I had money burning a hole in my pocket, the DC Solar bankruptcy let me buy Sunny Islands for $0.25 on the dollar (someone before me paid $0.10 on the dollar for them at auction), and the Devil found work for my Idle hands (got canned, was unemployed 3 months.) So I coughed up the money for a small battery bank - 20 kWh AGM cost me the same as 4x 6kW SI6048 inverters. It just seemed silly to put less than 20 minutes reserve of batteries on a 24 kW inverter.

Some people want to disconnect from PG&E. Very difficult and expensive unless they drastically cut consumption (especially for those with electric heat.)

With time of use prices varying 3:1 during the day, using batteries to time-shift power usage looks interesting. But except for DIY batteries, the battery costs more than the spread in rates. That's a net loss not a net gain, and it'll take a decade to even approach break-even.

I've decided that instead of making one kWh in the morning (when rates are $0.15/kWh) and saving it to use early evening (when rates are $0.45/kWh), I'm better off backfeeding the grid with three kWh (PV generated currently costs $0.05/kWh) and getting a credit that'll let me draw one kWh in the evening.

That said, If it gives a person contentment and keeps them out of whore houses and gives them something to do

Where's the fun in that ??

 

[Gazoo]

I used to remove the built in batteries and use much larger external batteries for longer run times.
Did you Build your inverter from scratch or used a board like the EGS or modified an existing unit?

I thought about buying a UPS from Ebay without batteries and doing the same thing. But I have pretty much settled on going the inverter/charger route. The cheap inverter I am currently using is 1000 watts...nothing fancy. Bought it off of Amazon and it's going back. It works well and all, but the fan noise is as loud if not louder than my vacuum cleaner...lol. Besides the main intent for buying a cheap inverter at the time was to test my cells.

Mate, seriously, good on you. What you say makes sense and is a good way to go about things for your needs and that is what is important.
What you are doing is well thought out and realistic and certainly was not what I had in mind or was talking about. Your options are limited and you have taken the best one in anyone's book.

How much storage you have so far?

Thank you. I didn't take anything you said personally...just wanted to point out what I am working on and what my use is for, and why I can't use a generator or solar. I would love to get into the solar side of things but for now it's not happening.

I have built an 8S 24 volt pack using the EVE 280ah cells. Even that is overkill but as I pointed out it is more of a project thing but will be useful if we have a blackout. It's been fun and I like to play with this stuff...safely of course. If you know off hand of any UPS's that would work well with a 24 volt pack I will take a look.

The problem I am finding with inverter chargers is all the conflicting stuff concerning grounding. I was looking at a Samlex EVO 1200 watt, and when I asked Samlex about grounding he told me I didn't need to ground the case because it's taken care of internally as long as it is connected to the grid. That part makes sense. But when I asked about unplugging from the grid during lightning storms he told me electrical safety would be compromised and to chat with an electrician...lol. That doesn't make sense since they are used in RV's.

I have had several UPS's in the past but none with extended run time options like the APC XL's. However I have unplugged the ones I have had from the grid and was never shocked. I don't know if they use isolation transformers. But it should not be that difficult to get the information I seek from Samlex and I will be calling them to make sure we are on the same page. I don't know if it was sales or a technician that gave me the information. I need to speak with one of their techs. I understand very little about grounding inverter chargers even though I have read mountains of information.

 

[GXMnow]

We all have our own reasons for wanting solar and/or storage. And it is certainly not always cost effective.
I looked into Tesla Modules, but the 6S config is just a pain. There just are not many inverters that work well with that.

A basic grid tie solar system used to be a pretty good investment. But with the changes in NEM 2.0 they kind of killed the major advantages. The "Time of Use" rate schedule really slams the pay off time period. For me it ended up nearly double. But I do get it. So many people around me have grid tie solar now, that I can see the "Duck Curve" causing trouble for the power company. Solar provides more than we need while the sun is shining, but then the sun goes down and people still demand power. We have been threatened multiple time with "Public Safety Power Shutoff" alerts to minimize fire danger when it is dry and windy. I have not had many issues yet, but we can see a time when they could shut us down for a week or more, like what happened in nor cal. So I did want backup power. I am using my battery bank to also give me "Power time shifting" to help offset the cost of the battery bank. It will never pay for it though. IF a big "IF" my batteries last 10 years, then they will come out to being nearly free, but I am not betting on that. Hopefully, the cost of batteries will come down some by the time I need to buy another bank. With all the new EV's coming out, who knows what will be around.

Since this thread was about killing a Tesla pack, I will try to stay on subject. The newer tech packs that Tesla is working on may end up being great for home storage. My inverter and BMS has a fairly wide adjustment range, so I can dial it in to many different chemistries. But I may have to rewire the banks to get the voltage right. I did that with my Chevy Bolt bank, re-wiring two 10S and one 8S into a pair of 14S strings. This whole thread started because the original poster changed the settings on his charge controller to "Lithium" without knowing what chemistry or cell count that was for, and not having a BMS at all. The result was pushing the 12S setup to 58.4 volts on a 16S LFP charge program. The lesson here is if you are going to work on a custom battery, you need to know what is going on. Every lithium batter pack needs a properly configured BMS to be run safely. If noting goes wrong, a BMS really does not need to do anything. Most will help balance the cells, but the more important part is the cell protection. If the OP had a BMS, his incorrect setting would have just resulted in a shut down. Without a BMS, he is lucky he didn't start a fire. Mistakes can happen. Be safe and double check everything, and for those times something does go wrong, having a second level of protection is never a bad thing.

 

[Hedges]

My cost to be connected to grid is $10/month, so that's $0.33/day.
Now that we're paid $0.04/kWh for surplus kWh at true-up, sometimes I get some cash to offset that.

If, considering time of use rates, I had a deficit at end of year, I fork over cash.

Between the two (kWh and dollar accounting) there was a dead zone, no money changed hands either way at true-up.

The new time of use schedule means I need to be a net producer of kWh, perhaps by a considerable amount, to avoid owing money for the dollar accounting. But if I get paid $0.04/kWh for that surplus it'll pretty much return my cost of "goods".

The gas is stove and water heater year round - if only those the bill tends to be $8. Furnace is gas too, but I've been heating with electric due to my surplus.

With our gasoline prices ($3 to $4/gallon), electric vehicles might save me money. But not unless my existing ones fail; capital cost of a replacement exceeds my fuel cost. When I have done major repairs (myself) it has cost about $800. Less than sales tax on a new vehicle. When I got my truck, diesel cost less than regular but now it's often more than premium. I stick with pure Dino Diesel to avoid possibly corrosive compounds. I put on very few miles.

 

[SG-1]

This is what can happen with no BMS & wrong charge settings

 

[stxShadow]

Hello to all of you .... i'm new to this forum and not a nativ speaker :D

I use Tesla Model S packs for some yeas now. My total pack capacity is around 40 kW/h consisting of 8 x 6s Tesla packs. I power my whole household with theses packs and 6 solar arrays. The inverter chargers and MPPTs are controlled by victrons DVCC (Distributed Voltage and Current Control). The pack is protected by a trip shunt which is controlled by a SimpBMS. Max Charge/Discharge Current is communicated to the inverters (from SimpBMS).

Here are some photos of the setup:



If someone has questions regarding Tesla packs: Let me know :D

CU

Jens

 

[GXMnow]

Any system that can store large amounts of energy can pose a danger. There is always this balance of trying to keep costs down and getting the best performance. No lithium battery system should ever run without a BMS that can safely shut the system down if a cell is going out of range. That is the very least we all need to do.

The Tesla battery modules are very well made, and should have no issue being run safely without needing the active cooling system at the current levels we run with solar storage. My system is currently running Chevy Bolt battery modules. Again, they are very well made, and should last years without any trouble. I am not using the cooling system that is used in the car either. Each cell can easily handle 60 amps, and I am running them in 6P, so 360 amps of charge current is within rating. I am charging at under 30 amps. Full load from my inverter would only top out at 140 amps. They run stone cold. But things can go wrong. Fuses and a BMS are required. And you must ensure you are running the correct settings. Chevy and LG have issued a recall on the Bolt due to 2 fires out of nearly 100,000 cars sold. Due to that, they have told owners of the cars to not charge above 90% until they figure out what has been causing the problem. Both fires were shortly after a full charge. I have lowered my full charge to just 85% and my BMS is set well on the safe side. Of course, I am keeping an eye on the Chevy LG news to see what ends up being their solution. My hope is it was a BMS and charging error. Obviously, my battery pack is sitting still in a garage, not bouncing around the street in a car. But if it is a mechanical issue with the pack assembly, it may push me to change out my battery bank a bit sooner.

Be safe, double check everything, and always use a properly set BMS.

 

[stxShadow]

Be safe, double check everything, and always use a properly set BMS.

Amen !

Never the less i will change to LiFePo4 for security reasons. SimpBMS works quite well with victron equipment but you never know. I think if my 8 packs caches fire (for what reason ever), it will burn down my whole house.

Jens

 

[GXMnow]

My LG Chem Li NMC battery bank is in a steel enclosure on wheels just inside the overhead door of my garage. If I ever get a temp warning from the BMS or the XW-Pro temp sensor, I just yank a plug and roll it outside. After intentionally setting off a few old RC LiPo cells, I have a pretty good idea how they burn, and I am fairly confident that even if the whole pack went up, my enclosure would keep the battery from burning my garage. But I still have multiple safeguards in place. The LG pouch cells rupture at a much lower pressure than metal cylinder cells like Tesla uses. They will fail sooner but at a lower energy, and they end up just spitting out a gas jet that might burn like a small torch flame. The Chevy Bolt pack then has a sheet of aluminum between every pair of cells which will help carry away heat and should greatly reduce the chance of runaway to more cells. One failed cell should be able to gas out and burn without the whole brick going up. 99% of all pouch cell failures are either overcharging, or physical damage to the cells. I have virtually eliminated any chance of either of those happening. The only other issue, that 1% (actually far less) is an internal cell flaw. This was the cause of the Sony laptop battery fires, and also the Samsung Note 7 fires. They were very high density cells, produced at very high speed, and tiny flaws in them allowed internal shorts to occur. Those were also in mobile devices where drops and knocks allowed the little flaws to get moved and puncture through the internal insulator between the anode and cathode causing the short. So even if there is that kind of a flaw in one of my LG cells, I am not knocking them around. They were built to live in a car, and survive a crash. Mine sit still, taking a very low C rate charge and discharge, between 40% and 85% charge. And yet, I am still closely monitoring them, and watching any news on the Chevy LG recall. I am not afraid of these burning my house with how I am using them, but they certainly do demand some respect. This pack is storing the equivalent energy of about a half gallon of gasoline. Spray a half gallon of gasoline with a paint sprayer across a lit candle and see what damage that can do. Stored energy needs to be respected.

I am always looking at battery options and watching where the tech is going. As soon as this battery bank gives me any trouble, it will be offline and I will look at replacement options. I got a great price on them, and if I get 5 years, I am doing ok. If I get 10 years, they were basically free. I almost bought 280 amp hours of cheap no name Chinese LFP cells, but I feel this is safer, is 360 amp hours, and I got it for half the price. Any branded quality cells were quite a bit more than that. So yes, I am taking a risk to save money.

 

[SG-1]

My cost to be connected to grid is $10/month, so that's $0.33/day.
Now that we're paid $0.04/kWh for surplus kWh at true-up, sometimes I get some cash to offset that.

The new time of use schedule means I need to be a net producer of kWh, perhaps by a considerable amount, to avoid owing money for the dollar accounting. But if I get paid $0.04/kWh for that surplus it'll pretty much return my cost of "goods".

Must also consider, are power prices going up or down in the future. Also that 0.04/kWh will it stay at that price as well.

When you consider all those factors, having a battery bank to store solar, then using it at night when in peak periods the choice becomes easier to make. Most people are not home during the day so any real benefit of having solar to use during that time is wasted.
We need to think smarter and beat the power companys at there own game.
Any excess after the batteries are charged can always be exported to the grid leaving you with a cheque from the power companys not a bill.

 

[stxShadow]

We pay 30 Euro cent / 36 US cent per kW/h in germany. So quite worth to use a battery :D

Jens

 

[SG-1]

I am always looking at battery options and watching where the tech is going. I got a great price on them, and if I get 5 years, I am doing ok. If I get 10 years, they were basically free. I almost bought 280 amp hours of cheap no name Chinese LFP cells, but I feel this is safer, is 360 amp hours, and I got it for half the price. Any branded quality cells were quite a bit more than that. So yes, I am taking a risk to save money.

The risk is minimal compared to using cheap chinese batterys that don't store the charge stated on the packaging. Some are lucky if they store half. Sometimes it is worth spending a little more for something decent.

 

[Europa]

Be thankful you didn't burn your house down battery is toast don't play with it... so not worth it especially for a novice. Please seek some local help for proper disposal of your battery. Seriously this is the best advise I can offer you.