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Your battery voltage is too low to run your washer . I have fuse for each battery in series and a breaker for each string of battery in parallel and a volt meter to each battery .Diy battery to work is not easy and need to watch the voltage all the time when the inverter is loaded because the battery voltage will drop and every battery will have a different voltage .
On 3/26/2022 at 5:30 AM, dickson said:Your battery voltage is too low to run your washer . I have fuse for each battery in series and a breaker for each string of battery in parallel and a volt meter to each battery .Diy battery to work is not easy and need to watch the voltage all the time when the inverter is loaded because the battery voltage will drop and every battery will have a different voltage .
Well, even when I was useing the lf4 batts the washer did the same thing even when the voltage didn't drop. But that is not what I was talking about on this topic anyhow.
Any suggestion on a resetble breaker that don't cost a arm and leg, cause I'll need to get roughly 8 of them. I'm really considering on doing a hybrid setup, I'm seeing a new thing or some what old school of useing lythuim to keep a set of agm batts topped off useing a higher voltage to a solar charger to charge the lower voltage.
What is a hybrid setup ? Your BMS do not work and you have no protection for the battery . You need to check the voltage of every cells and its a 216ah 12v 56 cells in a modual. All now wired solder together ? That mean a voltmeter reading on every one of the 56 cells . Your battery system is almost impossible to control . Someone else on this forum has battery that is hard to control . I have voltmeter on every battery (25 voltmeters) and still had to recharge at night to control the SOC .
1 hour ago, The Blind Wolf said:Well, even when I was useing the lf4 batts the washer did the same thing even when the voltage didn't drop. But that is not what I was talking about on this topic anyhow.
Like you said, battery voltage drop isn't the problem. (Your washer can't see DC voltage) AC Voltage Drop is. Put an LED bulb on the same Leg. You'll see a big flicker right when it stalls out. VFD's can be really sensitive boogers - they're not usually engineered with off-grid in mind. They expect minimal voltage drop, like what you'd get connected to a utility with a big turbine power plant. (Your 2KW surge is nothing to a 50MW turbine, but substantial to a 6KW inverter...)
5 minutes ago, dickson said:What is a hybrid setup ? Your BMS do not work and you have no protection for the battery . You need to check the voltage of every cells and its a 216ah 12v 56 cells in a modual. All now wired solder together ? That mean a voltmeter reading on every one of the 56 cells . Your battery system is almost impossible to control . Someone else on this forum has battery that is hard to control . I have voltmeter on every battery (25 voltmeters) and still had to recharge at night to control the SOC .
I think he means LiFePO4 + AGM in parallel. The AGM will [practically] stay 100% charge - only discharging when the LFP's are [>90%] depleted or under exceptionally high (In my case, surge > 400A @ 24v) load. This is the same setup I use.
By the way, regarding fires, LiFePO4's don't exhibit Thermal runaway like traditional NMC's. Specific [improbable] conditions must be met for a fire risk.
I think he means LiFePO4 + AGM in parallel. The AGM will [practically] stay 100% charge - only discharging when the LFP's are [>90%] depleted or under exceptionally high (In my case, surge > 400A @ 24v) load. This is the same setup I use.
I parallel my lithium ion battery to AGM ( 4 in series ) when the lithium ion battery go down to 53 volts .
9 hours ago, NotMario said:By the way, regarding fires, LiFePO4's don't exhibit Thermal runaway like traditional NMC's. Specific [improbable] conditions must be met for a fire risk.
From memory a lifepo4 cell needs to get up to around 200c before it goes into runaway, once there the temperature doesn't take off like a rocket, and the cell has little chance of spontaneous failure in the first place. NMC on the other hand is ready to go at around 150c (also from memory), the temperature goes orbital, and the cell has a well earned reputation for spontaneous failure at the slightest excuse. That much lower threshold for all hell breaking loose is a big problem for cascade failures.
There's a false sense of security in the off grid community that lifepo4 is safe and won't burn but that's very wrong. Subject either type to a fire and you won't have a good day with various nasty gasses being released along with a good dose of oxygen to stoke the fire, but I think the fact that the premises is on fire in the first place is going to be the primary concern.
Garcia has been playing with lithium cells for ages but that doesn't mean he understands the risks of 'li ion' compared to lifepo4. IIRC a person commented on one of his recent clips regarding the probability of thermal runaway increasing in a battery in relation to the number of cells in the battery and Garcia spent a fair amount of time deriding him for it. Despite playing with cells for ages Garcia has little understanding of probability maths and couldn't (and probably 😉 still can't) see the forest for the trees.
Despite playing with cells for ages Garcia has little understanding of probability maths and couldn't (and probably 😉 still can't) see the forest for the trees.
I see his DIY powerwall on youtube inside his house and that could be a diaster on a bad day . All my lithium ion ev car battery is outside a brick wall and concrete box .
Garcia has been playing with lithium cells for ages but that doesn't mean he understands the risks of 'li ion' compared to lifepo4. IIRC a person commented on one of his recent clips regarding the probability of thermal runaway increasing in a battery in relation to the number of cells in the battery and Garcia spent a fair amount of time deriding him for it. Despite playing with cells for ages Garcia has little understanding of probability maths and couldn't (and probably 😉 still can't) see the forest for the trees.
What really concerns me is people (like Garcia) and others believing that a "cell level fuse" is a perfect safety device for a large "18650 powerwall."
It really doesn't solve any problems, nor does it provide any usable safety. Yes, it WILL help in the event of a dead short across the pack.
And it will blow in the event of a cell instantaneously failing dead short. Problem there is that I've never seen an 18650 Li-Ion cell develop an instantaneous short.
The issue that we found with "recovered laptop batteries" are Li-Ion 18650 cells that slowly start to develop an internal short. This is identified by a single cell getting hot under normal charge voltage situations (I had one that would get very hot at 4.1v, but still held a full 2,200mAH). These won't blow a cell level fuse--but they WILL provide a very significant fire risk as they progressively get worse, getting hotter and hotter as time goes on. Eventually they'll explode and start a chain reaction fire.
Seriously, if you think about it even if you set a precise fuse (which there is no such thing) that would blow at 2.2A (ruining any sort of surge capability on the battery!), 2.2 * 4.2 = almost 10W of heat that the battery can generate WITHOUT blowing the fuse. For comparison, a small soldering iron is 15W...and with a cell fully boxed in a battery array, where are you going to be able to dissipate 10W of erroneous heat??
Case in point: I had a wall wart ("Makita 7.2v Ni-Mh drill charger") that suddenly stopped working. Opened it up, found that the AC fuse (proper fuse, not a length of wire!) had blown. Did a quick test, and bypassed the blown fuse (power surge, right?) with a bit of the transformer primary's magnet wire (#40 or smaller!), and the wall wart seemed to work just fine--provided voltage output, wasn't humming loud, etc.
So I reassembled the wall wart. Plugged it into the wall, connected the Makita drill...and forgot about it for a few hours.
Came back to a fully charged drill (i.e. the transformer was producing the right voltage, with a good bit of current)--but the scorching transformer had literally melted the plastic wall wart enclosure down, and done a serious number to the power strip I'd plugged it into. That magnet wire "fuse" hadn't blown.
There's a false sense of security in the off grid community that lifepo4 is safe and won't burn but that's very wrong. Subject either type to a fire and you won't have a good day with various nasty gasses being released along with a good dose of oxygen to stoke the fire, but I think the fact that the premises is on fire in the first place is going to be the primary concern.
Agreed. While LiFePo4 is considerably safer than Li-Ion (or especially Li-Po!), that doesn't mean it's impervious to disaster. I seem to recall having seen a fire-damaged LiFePo4 bus battery block...caused by the cells themselves. The safety factor here is that just a dozen or so cells were destroyed--the rest of the bank was intact. (If it had been a Li-Ion bank, there wouldn't have been anything left to talk about.)
A youtuber, this time based in Australia, was into building very large recovered / salvaged li ion batteries. Then one day he pointed a thermal camera at one and discovered the truth of what he'd actually built, a time bomb that was quietly ticking away. Cells were failing and turning into heaters. Fortunately he discovered it before it ran away and burnt his premises down.
A youtuber, this time based in Australia, was into building very large recovered / salvaged li ion batteries. Then one day he pointed a thermal camera at one and discovered the truth of what he'd actually built, a time bomb that was quietly ticking away. Cells were failing and turning into heaters. Fortunately he discovered it before it ran away and burnt his premises down.
Care to share a link just in case someone stumbles upon this thread?
For those reading: I'm not some "jaded stuffy armchair warrior"--no, I've actually dealt with "recovered" 18650 cells, ripping dozens of laptop battery packs apart and extracting the cells...then cycle testing all of them, writing the capacity on the outside of the case...then soldering them together into a bank (48v, ~50Ah--so about 336 cells in all). Made a decent ebike that could go over 70 miles on a charge.
However, as a direct result of my discoveries/findings through that experience (particularly the "slow heater" cells that just slowly get worse and worse), I will NOT recommend ANYONE to make "18650 powerwall" battery banks for any purpose or use. That is, unless you don't value anything else you have in the near vicinity of said battery pack...
...in other words, I like to be able to sleep at night 😉.
https://www.youtube.com/watch?v=BnJZBbDDVH8
This clip is from HBPowerwall regarding someone else's DIY recovered li ion battery and cell level fuses didn't save the day. Later clips from HBP see him pointing a thermal camera at his own DIY battery and finding cells going bad within a 7 day interval. All the batteries were well built, nothing crook about the construction. It was all due to cells failing internally. How many people here that are into this sort of activity point a thermal camera at their creation, every day? None, I'd guess.
Even new li ion cells can fail spontaneously, add in the recent spate of minor manufacturing defects from big names and it all gets rather scary.
From memory a lifepo4 cell needs to get up to around 200c before it goes into runaway, once there the temperature doesn't take off like a rocket, and the cell has little chance of spontaneous failure in the first place. NMC on the other hand is ready to go at around 150c (also from memory), the temperature goes orbital, and the cell has a well earned reputation for spontaneous failure at the slightest excuse. That much lower threshold for all hell breaking loose is a big problem for cascade failures.
Of course, if there's a fire near your batteries, you've already got a big problem on your hand. Granted, the batteries wont make it any better.
But i don't consider that to be a problem with the batteries. Or a significant factor in risk assessment for that matter. The NMCs are much more volatile.
I don't consider power generation (at residential levels) to ever be completely "safe". You're generating 1000's of watts of power - and likely dealing with 100's of amps. Any number of things could go wrong. Your batteries are just another factor to consider.
Recently i was reading about a MPPT Charger burning when running close to (but below!) it's maximum rated voltage of 200V. A MPPT charger that i currently use. 😕 Made me think a bit. Fortunately, i'm only running 136V, and my thermal cam doesn't show any sign of danger at the highest loads.
Care to name and shame the MPPT charger? There's not a lot of higher voltage MPPT chargers out there.
On 4/3/2022 at 5:30 PM, TheButcher said:Care to name and shame the MPPT charger? There's not a lot of higher voltage MPPT chargers out there.
Haha, well sure.
It's an EPEVER Tracer 10420AN. Apparently they've been lacking in the quality control department here lately.
Like with so many things, it's hard to say for certain if this was a product defect, or poor user installation. If it's a defect, whether it's an aberration or a one-off. At least in my case, it stays below 100f maxed out.
Nevertheless, at it's price point, you'll struggle to find anything more capable. So far it's served me well.
FWIW, i think everyone who can should carry a thermal cam to check these things out, especially to see possible stress points at high load. Compared to the cost of all the equipment and batteries, a nice thermal cam is a drop in the bucket.
11 hours ago, NotMario said:It's an EPEVER Tracer 10420AN. Apparently they've been lacking in the quality control department here lately.
Like with so many things, it's hard to say for certain if this was a product defect, or poor user installation. If it's a defect, whether it's an aberration or a one-off. At least in my case, it stays below 100f maxed out.Nevertheless, at it's price point, you'll struggle to find anything more capable. So far it's served me well.
I personally have two Epever Tracer 8420AN MPPTs. Like you said, for the price point, they can't be beat (fanless design, etc.)
One I bought new, and another I bought "for parts only." Turned out the problem with the latter was a failed SMD resistor on the DC input.
I also had someone send me the boards to an 8415AN that didn't work--and let's just say that it had widespread damage on the board (blown FETs, power supplies, etc.), seeming a bit like it got an overvoltage somewhere.
It is worth noting that while the PV input on the Tracer xx20AN units might be rated at 200v, also so are ALL of the parts on the PV input line. So the 200v rating is not a "safe max", but rather an "absolute maximum" rating. Their xx15AN units are rated @ 150v--with 150v parts inside.
Also worth noting that I had a Morningstar Tristar blow up on me (bright orange flash) after the umpteenth MODBUS restart command. Their customer service was exemplary...but it's worth noting that things happen even to "the big guys'" products too.