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Small Update from my Monthly Stats:
Original AIMs 12,000w inverter failed at 23,458 hrs of operation. The SGP 12,000w I got as a replacement for the AIMs achieved 23,950 hrs as of today. SGP is doing better than AIMS by 492hrs so far. :)

TMI: I got the original AIMs fixed and remains in storage as a backup.
 
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Aging battery: We're heading into day 4 of 106F/41C weather + a little forest fire smoke topping out at 86kwh PV instead of 93kwh recorded hi a few weeks ago.

At these temps, the heat-pump looses efficiency >102F? and pulls 100% power continuously. In these conditions, the powerwall min voltage drops a bit lower each 24hr cycle - loosing ground at ~10kwh/day more consumed than produced.
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TMI: At >110F/43C the heat-pump can't keep 72F/22C in house - we're had 115F/46C twice in last 3 yrs.

Decided to fool around and lower my normal 49.5v (3.54v/cell) low cutt-off to see if I could 'weather' this. This morning I hit 48.8v (3.49v/cell) but... got a huge drop on pack #2
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This is one of the oldest packs and is physically right near the main positive draw of the powerwall. Packs #1 and #2 have been stable/balanced the last 6 months - no issues other than age and 2,600+ cycles.

I'm trying to think how to extend the life of battery #1 and get more out of the powerwall - maybe move battery #1 to the a different location? Maybe replace pack #2 in particular?

Put an OPUS on pack #2 for the short term to avoid further drop and let's see how it recovers during today's charge.
 
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Both Pack 1 and 2 look problematic, just #2 is more so.

Would be good to pull them out of service and do a direct capacity test on them. Problem is, that pulls a whole battery offline when you kind of need it the most :(

We've been getting a lot of cloud/rains here (Fl) recently and I struggle to get the 2 batteries topped off (32kWH) in just a few hours. That's with 10kW of solar at my disposal. I'll be putting up the rest of the free low wattage panels to help extend the ground mount production.

But your case, it's probably a good idea to lower the bottom voltage periodically slightly to see if any weak packs show up. In your case, this could have lead to a battery collapse if had gone on long enough. At least you caught it before it could get that far.
 
Korishan said:
But your case, it's probably a good idea to lower the bottom voltage periodically slightly to see if any weak packs show up. In your case, this could have lead to a battery collapse if had gone on long enough. At least you caught it before it could get that far.
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Agreed. I'm thinking at this level of drop/sag, it could rapidly go worse, maybe <3.0v/catastrophic.
 
Generator Test Fail: Decided to test adding 10kwh to the battery to try to make it thru till morning as we should return to 100F/38C range tomorrow.

With 107F/42C outside (generator), 80F/27F at the battery room (Chargeverter), fired up the Honda 7000is (4800w) -> Chargerverter (83a) -> battery @ 52v and it ran for an hour before the charging stopped. I smelled ceramic burning but was hoping it was the yellow paint on the Chargeverter??...o_O

It wasn't, the Chargeverter plug fried....
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It was confusing to diagnose as the Chargeverter remained on because it was getting 120v on one of the 240v legs but of course it won't charge without both legs. My 1st guess was I fried the Chargeverter itself! but after dismounting it, I discovered the plug.

Put on a new plug and resumed charging.

Nothing like a real world test of the system to turn up issues. The Honda 7000is seems to be running smoothly in these hi temps (good to know). Keeping an eye on the solar room via camera.
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Made this morning still 100% on the solar system with yesterday's 88.4 PV + 10.4 Generator = 98.8kwh. Going to bottom out at ~49.0v (3.5v/cell) this morning.
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Pumped in 12ah to pack #1 and another 12ah to pack #2 via an OPUS to shore up yesterday's sag. Also paralleled in 30ah worth of cells to pack #2 to help shore this up longer term while I figure out what to do.

If I were to raise the charge voltage prior to the heat wave I would have enough range in the powerwall to make the 4 days - good experiment.

It's still amazing (to me), I can pick 88.4kwh out of the air at my home - hasn't gotten old yet. :)
 
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Suitcase Battery Update: Wife calls it the Suitcase 'Nuke' :)

Got it wired and running today. Weighs 40lbs (18kg)....
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The cells are 5a max discharge. At 18p14s in theory it can do 18p * 5a = 90a but went with 60a Midnite breaker to give me about 3000w max. The battery has 47.7ah @ 52v = 2.48kwh capacity.
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120a DALY BMS...
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Couple of issues....
1) DALY iPhone BMS from the Apple store didn't work! Frustrating!! It would see the Bluetooth but after connecting it just hung / no data. Spent a couple of hours - registering, trying various passwords, checking/re-checking my wiring trying to understand what was wrong. This is my 1st DALY and I didn't know how the app was supposed to work. Turns out its just a bad app!

Finally found an alternate "Smart BMS" iPhone app and it worked 1st time as one would expect - including the ability to change settings.

2) First charge with a 48v @ 15a (~800w) resulted in a balanced battery (30mv diff) moving to a 110mv out of balance. The main positive 18p voltage gradually separated from the other 13s groups as things charged from 3.6v/cell to 4.1v/cell. Not sure why the main positive would do this.
Have tried to set the DALY to do multi-day constant balance, but it's slow going. After 8hrs it's only come down 4mv from 110mv to 106mv max difference.

Deployment....
Once it's balanced, I'm going to swap out my LifePo4 50ah powering my APC 3000 with the suitcase and see if I have a backup.
 
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Smoke hurts PV. Here's a revealing Google graphic of fires/smoke across Oregon at this point in the summer. They say Oregon has surpassed the past record of 2.2 Million acres and we're only 2/3 of the way thru fire season.
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I'm located ("Me" above) just on the western edge of the smoke so far this summer. Picked up a full 92.2kwh of PV yesterday.
 
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Yeah that sucks. It diffuses/reflects the wrong light frequencies to be picked up. Definitely one of those things where a few extra panels and/or other sources of input are helpful (wind/hydro), if possible to install in your area.
Hopefully the fires are put out soon
 
Brand New, Battery #12 hooked up this morning. This expands the Powerwall to 3120ah * 52v = 162kwh. However, there is loss (20%?) over the last 8 yrs and estimated actual capacity ~130kwh. Including the trailer (27kwh), my journey has reached 18,000 cells at $175/kwh.

I blame @Wolf for donating several (really good shape) OPUSs, feeding my addition, and leading me to do these last 2 batteries. Unfortunately, the OPUSs continue to work perfectly - not sure what's next. :cry:

Batrium at 164 longmons working smoothly....
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Pack #163 somehow didn't get discharged to 3.7v the same as the others and have an OPUS on it to bring it in line :)
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OffGridInTheCity said:
Brand New, Battery #12 hooked up this morning. This expands the Powerwall to 3120ah * 52v = 162kwh. However, there is loss (20%?) over the last 8 yrs and estimated actual capacity ~130kwh. Including the trailer (27kwh), my journey has reached 18,000 cells at $175/kwh.

I blame @Wolf for donating several (really good shape) OPUSs, feeding my addition, and leading me to do these last 2 batteries. Unfortunately, the OPUSs continue to work perfectly - not sure what's next. :cry:

Batrium at 164 longmons working smoothly....
View attachment 34331

Pack #163 somehow didn't get discharged to 3.7v the same as the others and have an OPUS on it to bring it in line :)
View attachment 34332
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Congratulations 😊👍

Is this really your very last battery pack you're making?
 
kje said:
Congratulations 😊👍
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Thank you. One of the few 'addictions' that get a congratulations :cautious:

kje said:
Is this really your very last battery pack you're making?
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Thinking of buying a 'bug-out' property.... a seasonal cabin kind of thing. I could deploy my 3,000 cycle batteries to this setup and at limited number of days per year, these might serve a long time. This would make room for new ones at home!.

Wife's not on board yet and not sure I want to take on the 2026 US extensive 'rules'/'permits' for undeveloped property. But I am looking for a project.
 
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OffGridInTheCity said:
Thank you. One of the few 'addictions' that get a congratulations :cautious:


Thinking of buying a 'bug-out' property.... a seasonal cabin kind of thing. I could deploy my 3,000 cycle batteries to this setup and at limited number of days per year, these might serve a long time. This would make room for new ones at home!.

Wife's not on board yet and not sure I want to take on the 2026 US extensive 'rules'/'permits' for undeveloped property. But I am looking for a project.
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My advice would be whatever you buy to have it be in a condition that you can enjoy now, and projects you do just add to an already 'comfortable/liveable' state, that is low maintenance. My second (someday retirement) house is finally enjoyable... and it makes a huge difference.

(Also, DO NOT buy property next to a bamboo forest! A crazy amount of my time is spent dealing with runners. I need to install a bamboo barrier. ) :)
 
Fukuokian said:
My advice would be whatever you buy to have it be in a condition that you can enjoy now, and projects you do just add to an already 'comfortable/liveable' state, that is low maintenance. My second (someday retirement) house is finally enjoyable... and it makes a huge difference.

(Also, DO NOT buy property next to a bamboo forest! A crazy amount of my time is spent dealing with runners. I need to install a bamboo barrier. ) :)
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Do you have problems with 'security' (vandalism, theft, etc) when you're not there?
 
OffGridInTheCity said:
Do you have problems with 'security' (vandalism, theft, etc) when you're not there?
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A "Runner" is a bamboo offshoot that starts growing from the roots that grows over. It's very similar to how grass rhizome grow. Afterall, bamboo is a grass. If you don't put a barrier down, the root will grow over to an unwanted spot and could cause damage as the new growth shoots up, and bamboo is a very fast growing plant, so damage can be done in months, or even weeks, compared to a tree growing where it's not wanted.
 
OffGridInTheCity said:
Do you have problems with 'security' (vandalism, theft, etc) when you're not there?
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I've never had any problems. It's in a place that you could leave your doors unlocked and not have to worry. I still lock up though, and am securing my battery box, as it's a hefty investment for me. It's also one of the reasons I'll put the solar panels on the roof, and not on ground mounts.

I'll eventually get ISpy up, using old webcams, as a cheap remote monitoring/security system. It can be configured for motion detection alerts. I'm not sure what the newer versions can do, as I was messing with it 10 years ago... I still have old versions, which will work great for what I want. :)

If I was back in the States, I'd definitely be using it right away as a security system. (And post signs saying it's active as a deterrent)
 
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