timselectric
If I can do it, you can do it.
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16 cells plus shipping was just under $3k.
Biting the bullet. Doubling my battery capacity $$$$$$
- Thread starter EPicTony
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timselectric
If I can do it, you can do it.
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Absolutely right.Maybe after the inspection, some DIY is in my future, can never have enough, right? …
how much of a tax credit are you getting per battery pack? I was looking at using the Ganfeng grade B 280ah cells at 18650 store. I figured i could make a pack with BMS for $2200 (im estimating tax) unless I'm missing something?
Many (most?) state don’t charge sales tax for solar equipment. You can take off 30% for solar from your federal income taxes carried over up to 10 years. Installation cost too if you hire someone.
EastTexCowboy
Solar Wizard
I'm pretty sure you can include anything else related to the install such as wiring, panels, breakers, etc.
timselectric
If I can do it, you can do it.
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30%
Yup, and your insulating rubber cowboy boots.
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that works on anything solar related. even these DIY batteries?
timselectric
If I can do it, you can do it.
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Yes, and everything else needed to build it.
There is an amazing sense of accomplishment when you build your first battery pack. Granted there is a little nervousness the first time you start your inverter. Once things are up and running you are hooked as you start to think of the possibilities. Especially when your better half sees what is possible.
This thread is dangerous...I am getting a itch to increase my battery bank...MOAR LifePO4 pur favorrr... 
Prices has gone up the last year though...was cheaper a year ago.
Buying a 15S2P (prebuilt) with 200ah is around 4000,- Euros atm.
Hoping to get lower with DIY myself.
Prices has gone up the last year though...was cheaper a year ago.
Buying a 15S2P (prebuilt) with 200ah is around 4000,- Euros atm.
Hoping to get lower with DIY myself.
this is awesome! i figured since it was all DIY stuff and not "installed by a professional" it wouldnt count. i was going this route anyways, this just makes it 30% better!
Yep, wiring , panels, all hardware, labor. Pretty much anything related to the solar install goes for the 30% tax credit.
The only gotcha is that you only get a credit against taxes you owe or already paid. If you exceed this you can just push the excess onto the next year (or years).
EastTexCowboy
Solar Wizard
I'm going to take a vacation, errr, I mean business trip, to Kentucky to look at, I mean evaluate, Tim's setup and write it off as part of the solar expense.
Don’t forget to write off the horse’s feed and stable fees for your solar exploratory travel.
OffGridForGood
Catch, make or grow everything you can.
If you have the space, maybe you can do both options: more factory built server racks, AND a DIY one, doesn't have to be 280Ah cells, just get some 100Ah cells ETC and make one for the heck of it, if you have the time and space.
I found it really enjoyable to build, and test, checking those DIY batteries after they have been running awhile and seeing a few millvolts cell deviation was pretty satisfying got to say!
The other option is make up some DIY batteries for a camper, gives you a chance to fit them to the space, learn some stuff, and have fun all at once. (ok if building battery packs and setting up BMS etc counts as fun!)
timselectric
If I can do it, you can do it.
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Building anything with your own hands is always rewarding. I really like things that are done my way.
EastTexCowboy
Solar Wizard
I'm on board with that. I gutted and completely remodeled our previous home back about 18 years ago and did 80% of the work myself. Built all the cabinets, fabricated the solid surface countertops for kitchen and all the bathrooms, did all the electrical and plumbing, hung the drywall and did all the finish carpentry. It was a beast that took me the better part of two years but I wouldn't change a thing. I did hire some of the framing done for a couple add-ons and the roofing. It was just too much to tackle by myself and having a business to run at the same time.
OffGridForGood
Catch, make or grow everything you can.
First I got two factory racks to get me started, then I built one DIY 280Ah, then a second, now completing my third...I have space for two more...does this qualify as an addiction?
OffGridForGood
Catch, make or grow everything you can.
For ETC - maybe there is a third option: Sepos Rack kit.
EastTexCowboy
Solar Wizard
I've looked at those before but I'll take another look. I've already got a few of the shelving units like Will used in his video, except mine are the typical gray instead of Dewalt yellow and have more shelves. I was thinking I'd use that since I already have it.
timselectric
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I don't think that Andy (off grid garage) likes the BMS that comes with the kits.
OffGridForGood
Catch, make or grow everything you can.
I thought about your comment Tim, had to go back and re-watch Andy's Seplos vids.
Andy comments early in the vid that the Seplos'BMS 'can communicate with several different Inverters' (user selectable) although at that time he also says 'I don't know why, but the BMS can talk to the Inverter for some reason'.
I realize in Andy's case, he built his own batteries and was very hands-on with his parameter settings, going so far as to test what these settings should be in the first place, and then setting up his system based on his findings.
For most of us, though, we don't use the BMS to set the control of the battery charging/discharging, we do this with the inverter settings, and we rely on the BMS more as ack-up protection in the event of a run-away-cell or failure of the inverter to limit charge/discharge correctly, and to control cell balancing.
Going back to the video, Andy's beef with the Seplos seemed to be that they preset values for their BMS that he didn't agree with.
For ETC and others on the forum, they may not share Andy's view on the Seplos BMS or how it needs to be configured to work with their inverters.
Something to investigate first before making the (sizable) investment in a Seplos kit for sure. I believe from following you on the forum that like myself we are happier to source our own (lower cost) parts for DIY batteries, including a BMS that suits us, rather than the Seplos option.
Still, Seplos is an entry-path to DIY rack batteries for many I suspect, one that removes most of the guess-work on what they will need to put a complete functional battery together.
If your batteries are enough to get you through a full day without sun, I’d think what you need is more solar panels, not bigger batteries…
At least price it out but I suspect doubling your solar array will cost you less than doubling your battery capacity…
TorC
Solar Enthusiast
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A sunny day can easily produce 3-4x+ what a cloudy, or worse, rainy day can. Being able to take better advantage of that sunny day is quite likely to be more practical than trying to eke out a bit more production on a cloudy day. Especially when at a mere 24-28hrs autonomy, where a single bad day is a system killer.
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