DIY batteries a lot cheaper?

YouNRG

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Sep 9, 2021
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So, I’m seriously considering building a DIY battery. Watched Will build a few on YouTube and it looks like fun, and a good learning experience. A while back Will built a 12 volt, 200 amp hour battery with Fortune cells and a Overkill BMS. The 8 cells cost about $960 ($120 each), and the BMS another $142, which totals $1102. The Overkill BMS also has Bluetooth and a great app. Then I saw him review an SOK 12 volt, 206 amp hour battery - which he highly recommended - at a cost of $1029. In that review video he states “you can make your own battery for much cheaper”. I’ve also seen many other YouTube videos where this is stated as well. So, I’m a little confused, and am probably missing something very obvious. Am I comparing apples to apples? Can someone please shed some light on this subject. Thanks!!
 

enough

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Dec 25, 2020
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Fortune cells are super premo and much better quality than the cells in the sok. To compare the sok 12v 200a with a diy battery, you’d want to compare with the cells on Ali express. I would not recommend BLS battery, but for an example, 4x 200ah 3.7 v cells are $525 shipped. +$120 BMS and other material is ~$700 total.
 

chrisski

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Aug 14, 2020
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Making your own battery is cheaper. It is a lot of work.

Ordering cells, waiting months for them to show up, a couple of weeks to balance. Then there’s the costs that aren’t talked about in the videos like tooling up with crimpers, heat gun, drills, etc. Even with those expenses it was cheaper. I did not get 1/5th or 1/4 the price like others claim, but the real cost for me will be at least 50%.

I am findint building my 280 ah 16s pack for my RV is as much work as installing the rest of the system. Every think I do I’m having challenges. One of the ones is attaching the BMS to the battery. Cases weren’t available for a smaller battery I built, so I made one out of popsicle sticks. I have a 3D print file for the bigger BMS.

If that type of stuff appeals to you, go for it. I doubt you’ll really see saving 80% though Once all costs are considered.
 

kenryan

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It seems to me that only very recently batteries that are much, much cheaper have become available. The big savings comparisons come from comparing to premium batteries like Battleborn (I choose them only because they are high priced). Some will say the cheaper batteries are lower quality, and they are probably correct. But from what I have seen, ordering your own cells is a crap shoot. You never really know what you are going to get until you get them. I have 8 X 280 ah cells ordered. It seemed like right after I ordered them I started seeing a lot more inexpensive (relatively) batteries coming to market. I am stuck now, but if I could roll back the clock I would just wait about a year and re-evaluate the situation. If the trend continues, soon it won't make economic sense to build your own.
 

HRTKD

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When I bought/ordered my cells last year (around June 2020), there was a large disparity between DIY and off-the-shelf. My 560Ah of DIY cost me $1100 (eight 280Ah cells plus two 120 amp 4s BMS). A similar Ah battery bank from Battleborn would have been almost $5,000. I think I made the right decision. But I like to think I'm mechanically inclined and can learn new skills. It took me a bit to come up to speed on how to build a DIY battery.
 

enough

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When I bought/ordered my cells last year (around June 2020), there was a large disparity between DIY and off-the-shelf. My 560Ah of DIY cost me $1100 (eight 280Ah cells plus two 120 amp 4s BMS). A similar Ah battery bank from Battleborn would have been almost $5,000. I think I made the right decision. But I like to think I'm mechanically inclined and can learn new skills. It took me a bit to come up to speed on how to build a DIY battery.

Another good point that the larger the battery - the more money savings. When you get down to a 12V 200AH, 100AH, or lower battery you aren't going to be able to save as much money due to the fixed costs, like the BMS, enclosure, your time, etc.
 

NOLA_Castle

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Another good point that the larger the battery - the more money savings. When you get down to a 12V 200AH, 100AH, or lower battery you aren't going to be able to save as much money due to the fixed costs, like the BMS, enclosure, your time, etc.
I agree with "enough", plus defect of every component, you need to deal with. And for first time builder, you may need an extra fund to cover your Ooops. Basically, you are the battery manufacturer, you need to know what you are doing.
 
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DLTooley

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Jan 12, 2020
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The 280ah cells are the best value, with some trade offs. There have been a lot of substandard cells on the chinese Ali sites recently, I believe also Amazon. The Luyuan 280ah cells and the JBD BMS would be my comparison items - check out in more depth and others on this forum.

While quality cells direct from china have gotten more expensive, the pre-made products available in the US have gotten cheaper. Ampere Time and Chins would be the one's I'd look at, in addition to the SOK.

Another thing about the quality products is a lot of the fine tuning stuff that's also detailed on this site is not needed. Those techniques, and the equipment to do it, can make those bargain cells work but its more than I wanted to take on.
 

TomC4306

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Mar 2, 2021
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I built a 48v, 150ah battery for less than $1500. 7.68 kWh.
$1000 for the cells, 150 for the bms, 50 for a 150a class t fuse, 50 for a switch and a couple hundred for wire, crimps and tools.
Compared to Battleborn at $4000 for one third less capacity.
Plus, it's fun!
 

NOLA_Castle

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Most insurance companies are looking for UL certification. I don't think DIY can be certified for UL.
 

YouNRG

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Hey everyone, thanks for responding so quickly. I really appreciate the information and insight provided. It looks like most are comparing DIY prices against the expensive Battleborn batteries. Expensive, yes I know - I bought two last year for my build of Will’s 2000 Watt, 24v Off-Grid Solar Power System. So I can see the cost savings of a DIY battery compared to this one. Based on the responses, I think I’ll be building with Fortune Cells and the Overkill BMS. About the same cost of a SOK, but much higher quality, and I love the Bluetooth capability and app. Haven’t decided if I’ll go with 12v or 24v yet. After that, I am planning on adding a much larger configuration for additional storage and the capability of running a small Mini Split a/c for a shed I’m planning on building sometime this year. I will keep you posted.
 

50ShadesOfDirt

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Jan 8, 2021
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To jumpstart my projects, I ordered the SOK 12v100ah (for smaller projects) batteries, and the AmpereTime 12v300ah (for the house battery bank). Both got here fast (SOK within a month), A-T within a few weeks.

Both brands are great performers in our homestead, with 120a draw (SOK) and 200a draw (A-T) ... handles everything we throw at them. These two brands have been good to us ...

A-T had a BMS issue on one battery ... it got swapped under warranty; no problem in getting it replaced (just took time and effort to get the swap done).

I do want to build out my own as well, but I recognize that this will be a "project", over many months. Ordering these other brands got me up and running right away, and off of Lead-Acid batteries ... what a nightmare of maintenance for those, thankfully fading from memory.
 

Rich585

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Mar 16, 2021
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Ontario Canada 🇨🇦, somewhere near Ottawa
Hey everyone, thanks for responding so quickly. I really appreciate the information and insight provided. It looks like most are comparing DIY prices against the expensive Battleborn batteries. Expensive, yes I know - I bought two last year for my build of Will’s 2000 Watt, 24v Off-Grid Solar Power System. So I can see the cost savings of a DIY battery compared to this one. Based on the responses, I think I’ll be building with Fortune Cells and the Overkill BMS. About the same cost of a SOK, but much higher quality, and I love the Bluetooth capability and app. Haven’t decided if I’ll go with 12v or 24v yet. After that, I am planning on adding a much larger configuration for additional storage and the capability of running a small Mini Split a/c for a shed I’m planning on building sometime this year. I will keep you posted.
For your larger system, building your own will overall save money and you know what you got quality wise. The cheap sub $500 batteries are temping but watching Will’s reviews and breakdown of internal components shows that you still get what you pay for.
 

RayfromTX

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Jul 17, 2021
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117
I haven't yet seen a ready made battery that has the combination of features and components I want. For instance, today I saw a new product that offers 9.6 KWh for an introductory price of 3,100$ plus tax and shipping. It is made with 50ah 4p15s. That means there is no individual cell monitoring. I found no evidence of a class T fuse. It does have a layout on the control panel that suggests it may be a Seplos BMS or some version of that type and the fact that it says that 15 of them can be paralleled is further evidence of that. I suspect that the cells are laser welded into the unit which, if true, makes self service next to impossible.

I'm not sure if what I'm building is a Cadillac version but it's definitely a souped up Buick. Nah, it's a Caddy. It will cost around the same per KWH if I were to charge 75$ per hour for my labor, which I do. I would definitely prefer the choices I made for the build compared the the choices the manufacturer of the ready built made for their build. Their price is going up to 3,900 plus tax and shipping as soon as their limited supply is exhausted.

I'm glad I decided to DIY my system but I do this kind of thing for a living so it is not quite the same as it might be for others. My career has been based on building one of a kind luxury homes where every day we have to figure out how to do things we've never done before from materials we've never seen in ways that won't create future problems or unacceptable risks. This site has been helpful in sorting through some of the pitfalls and dark alleys.
 

Just John

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Aug 15, 2020
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2,381
So, I’m seriously considering building a DIY battery. Watched Will build a few on YouTube and it looks like fun, and a good learning experience. A while back Will built a 12 volt, 200 amp hour battery with Fortune cells and a Overkill BMS. The 8 cells cost about $960 ($120 each), and the BMS another $142, which totals $1102. The Overkill BMS also has Bluetooth and a great app. Then I saw him review an SOK 12 volt, 206 amp hour battery - which he highly recommended - at a cost of $1029. In that review video he states “you can make your own battery for much cheaper”. I’ve also seen many other YouTube videos where this is stated as well. So, I’m a little confused, and am probably missing something very obvious. Am I comparing apples to apples? Can someone please shed some light on this subject. Thanks!!
I can share what I'm doing. I just built one of these a week ago (although with grade B cells). The finished results are quite nice, and prompted me to order 3 more of the battery kits.

First, grade A cells:


Yes, I'm sure you can order grade B cells for much cheaper. I'm going with grade A myself. Amy has quite a long thread here, and delivers what she says she will.

Battery box kits (they actually sale everything you need):


JBD 150 amp BMS (you don't actually want to run your cells above 0.5C or 140 amps).


The ones with grade B cells I'm giving to my grandson and sister along with an MPP PIP – 1012LV-MS, cables, some cheap 100 watt panels, etc. Especially my daughter/grandson have had power outages from hurricanes, and that should keep the fridge and TV running for them.

For myself, I'll probably use grade A cells and put a few in series for a 24v all in one.

A 280AH battery at 12v with a quality BMS is nothing to sneeze at, especially since you can run those BMS in series. Add matched grade A cells, and I suspect that even in series they will stay balanced quite nicely.

I have no financial interest in anything, I'm just very pleased with the quality of everything I've linked here, and would highly recommend them.

Edit to add, I'm going to check and see if the EVE 304AH cells will fit, or if they have plans for a plate to make them fit.
 

Just John

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Aug 15, 2020
Messages
2,381
Fortune cells are super premo and much better quality than the cells in the sok. To compare the sok 12v 200a with a diy battery, you’d want to compare with the cells on Ali express. I would not recommend BLS battery, but for an example, 4x 200ah 3.7 v cells are $525 shipped. +$120 BMS and other material is ~$700 total.

You might want to check these out, they look quite nice. I haven't enquired about pricing.

 
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