For the second part of my Home Solar Project, I ordered batteries and racking for the batteries.
- Options Evaluated
- Which did I choose?
- Assembling the rack
Ampere Time 12v 200AH Battery (Amazon Link) = 300$ / Kwh
Last year, I actually put together a portable power supply / UPS for my servers using this battery. I have no issues or complaints- it works exactly as expected. It has great capacity, for a pretty good price.
Overall, it costs around 300$ per Kwh of storage.
This is a pretty cost-effective option.
I will note- Chins batteries are pretty identical.
Will Prowse Video:
EG4-LL 48v – 100AH = 341$ / Kwh
The EG4-LL batteries are 48v rack-mountable batteries, with a total of 5.12kwh per battery. The form factor leads to being able to put together a quite dense storage solution, which doesn’t require nearly as much footprint as opposed to using the above batteries.
One of the features which really sold me on these batteries- They offer multiple solutions for communication. You can chain the batteries communication ports together, which can be connected to your inverter, allowing all of the components to talk together.
As well, the batteries include a LCD panel, which displays lots of useful information such as individual cell voltages, temps, etc. There is also LEDs to display the current battery state of charge.
The price here, works out to 341$ per Kwh of storage. While, this is more than the above Ampere Time battery- this battery has MANY more usable features.
I will note, these batteries are the same as Gyll.
Building your own = 120-200$ / Kwh
Building your own battery packs is a topic I see very frequently…. and, for good reason.
Why? Because you can generally build a complete system for FAR cheaper then you would otherwise be able to do.
If, you were to want to take this route, the cells are generally 3.2 volts each. I would recommend building 48v cell packs to reduce the amount of copper required to connect everything together, and to improve the overall efficiency. (48v inverters are generally smaller and cheaper as opposed to 12v).
So, 48/3.2 = 16 cells needed in series to hit 48v. = 51.2v maximum.
For around 3,500$, I found a random seller on aliexpress, selling 32 * 280ah cells. This would be good enough to put two strings in parallel, for a total of…
51.2v * 280 ah * 2 sets = 28.672 kwh of capacity, for 3,500$.
Your total cost here, would be around 122$ per kwh, which is under half of the above solutions.
BUT, there are a few more things to factor in.
You would need… a good BMS, bus bars, and a mounting solution.
You also have to wait months for a boat to arrive from china, you have to HOPE all of your cells arrived un-damaged, and unbloated…. and, overall, you have to accept the risk.
In the event you do received damaged cells, getting replacements or refunds may be a huge ordeal. Having to ship cells back to China, generally means…. its cheaper to just accept the loss.
In addition to the above risks- you will also be paying between 100$ -> 500$ for a good BMS solution.
EG4-LifePower4 Lithium Battery – 283$ / Kwh
Compared to the EG4-LLs, these batteries are only 283$ / kwh compared to 341$ / kwh.
I would expect roughly the same performance as the EG4-LLs, but, with fewer features. I personally, went with the option for more features.
With the exception of the missing LCD screen, and a few less ports- the only real difference I notice between these, and the EG4-LL batteries- is the warranty. The EG4-LLs have a 10 year warranty, while these EG4-LifePower4 batteries only carry a 5 year warranty.
Relevant Will Prowse Video:
Battle Born Batteries
I really have never heard anything negative regarding the quality of capabilities of battle born. If you are adding solar to an RV, these are likely one of your best choices due to the inclusion of heating elements in the batteries. However- for the bulk-capacity needed for a home- This solution isn’t very cost-effective.
The 12v heated cells, are… around 790$ / kwh, which is around double of some of the other options.
Like battleborn- Victron produces high quality components. Also- like battle born, these components have a premium price tag.
Having used Victron components in my previous Portable Power Supply / UPS, the Victron components were extremely flexible, and easy to use. They also integrated extremely well with other systems.
But- for the bulk storage needs of my house- I cannot afford the price premium here. If price was not a factor, I would likely opt for Victron, due to all of its potential integrations.
Storz 10kwh – 1,500 – 2,000$ / Kwh ESTIMATED
So, originally when I reached out to my solar installer, Their recommended battery was the Storz 10kwh.
While, I have not heard anything negative around these batteries…. and they do have a great warranty (15 years), I felt they were a bit pricy.
While, I cannot find any publicly available information, and I was unable to get the exact price of this solution, I estimate their 10kwh solution would cost between 15-20,000$.
I don’t know how much was parts / labor / etc., so, this is just a ballpark estimate…
Tesla Powerwall – 851$ / Kwh.
The Tesla Solarwall, has 13.5 kWh of capacity, and costs around 11,500$.
This option has fancy apps you can look at on your phone to see its performance. While, this option has a few fancy features- I don’t like the idea of the battery / inverter / everything being an AIO solution. I like the idea of being able to choose a different vendor’s inverter depending on the price / features / availability.
As well, Tesla has been receiving a lot of negative press lately regarding warranties, shoddy solar installations, etc. In the end, I will pass on this option.
Which did I choose?
In the end, I went with the EG4-LL batteries.
I felt it has the best balance of available features, performance, and warranty. I wanted something that looked nice, and I really enjoyed the rack-mount enclosure also offered by Signature Solar.
While, I debated on the cheaper Ampere Time / Chins batteries- I really liked the idea of a simple, dense rack of batteries in the garage. And- while the EG4-LifePower4 batteries offered a better price, I like the idea of the extra features offered by the EG4-LL batteries.
I… am a sucker for features.
Assembling the rack
Since, I decided to choose the EG4-LL batteries, It was only fair to also pick up the branded rack to go along with them. So…. lets put it together!
The rack itself, was made from 16ga steel, and is extremely sturdy after you get it put together.
I didn’t take step-by-step instructions on putting this together…. If you are looking for a step-by-step guide, this- isn’t going to be for you.
Issue #1 – Door Lock Clearances.
After getting the rack assembled, I noticed the door lock clearances were really bad. With the door shut, there was nearly 3/4″ of play. If you pulled the door hard enough, it would open regardless of being locked.
While, my intentions isn’t to build a perfectly secure cabinet for my batteries- I did want the door to shut nice and snug, instead of flapping around in the wind.
The first step to fixing this issue- I added an extra washer on the back of the lock. As it came, there was just a hair too much play for my taste, which makes it sound “Jingly” if you rattle the door. But- this little washer I had laying around, worked perfectly to take up the extra slop.
After adding the extra washer, this took nearly all of the slop out of the locking mechanism.
Next, I moved the “Latch”
In the below pictures, the holes on the left, are where the latch was originally mounted. After crawling in the rack from the back, I realized I could move the bracket back a bit- and still have plenty of clearances.
Because, the once very loose fit, was now an extremely tight fit, I took a pair of channel locks, and slightly bent the locking lever, so that it could more easily “catch” the “latch”
Looking in the rack from the back, You will notice- it is now an extremely tight fit, and will not rattle at all.
The extra bend, helps to ensure the lever can easily catch the backside of the latch.
Overall, this minor tweak took me 10 minutes to figure out- and removes essentially all of the “noise” from the door.
My expectations aren’t to make a perfectly secure door… but, rather, to just remove the noise from it, and to make it shut tightly.
Issue 2. #2 Phillips Bits.
If- you are like me, and you buy a bunch of cheap tools from Amazon and Harbor Freight- because you don’t want to pay the premium for a well made tool- Do yourself a favor and buy extra #2 bits.
You will need them. 🙂
Make sure you have a good drill.
I personally use a Milwaukee M18 Fuel 1/2″ Drill. I found for this- the best torque setting was “20”. Any more, and it would snap the bits in half. Any less, and the screws wouldn’t be fully tightened.
AFTER breaking 5 of my chinesium #2 Philips bits- I went ahead and ordered a few dewalt #2 bits. I have had great luck with all of my tools and bits from Dewalt… Given, there are 25 of them, for only ~50 cents each- I imagine the quality has to be at least a step above the cheap ones I broke assembling this rack. It never hurts to have a few extra bits laying around.
Lastly- the cheap extensions… I had a few no-name ones, which were hardly magnetic, which got sloppier for each screw I drilled. I picked up a few DeWalt replacements for 3$ each.
Oh, and, when assembling this rack, and mounting the batteries, I highly recommend either having a helper, or at least some method for helping you move everything. These components are HEAVY!
I don’t yet have an inverter to connect every time to, so- the batteries are sitting here turned off.
Hopefully, pretty soon, we can get the inverter / panels up. Will have to wait for part 3.
Final review for this rack 4/5.
The rack itself, has a heavy, sturdy construction of 16ga steel.
The instructions, are nearly non-existent for assembly though. I essentially had to figure out most of the details myself, which wasn’t too hard, given there are only so many parts included.
I did have to tweak the door mechanism to properly shut, without rattling. However, this was a pretty easy tweak.
Once the rack was assembled, the battery slid in with no issues, and very good tolerances.
Overall, I would recommend it.