i think the premade packs would be better compared to raw cells in combination with a box kit like the seplos mason (or something similar). the premade eg4 is $3400+, where the new cells+box combo is over 35% cheaper at somewhere around $2200 for the same capacity.
Continuing DIY or give up DIY to buy already assembled battery?
- Thread starter Rain@
- Start date
I priced out a 16S w/ 304Ah EVE cells w/ Seplos 200A BMS, box & display and it's just shy of $2k shipped to the center of the country. It's approaching 50% cheaper (or, distancing itself from 50%? looks like prebuilts are dropping at a slightly faster rate than full DIY kits).
Last edited:
you definitely found way better pricing than i could, though i just priced the entire mason kit directly from seplos and unused cells from 18650batterystore.
i think we will see prebuilts prices drop at a faster rate because there are still higher margins, as the supply options are limited but are growing every week. but i think diy kits will definitely still be a substantial cost savings. at least thats my take on it.
shadowmaker
Solar Addict
You are comparing DIY to UL listed premade. Why not compare DIY to non UL listed premade: OP claims LFP 14,33kWh wall mount under 150$/kWh all included with US based stock
I really hope these kind of batteries are getting more available to US, because currently you are getting screwed by vendors over there.
I’m stubborn and sometimes an idiot, so I chose to DIY as much as possible.
In reality, I don’t look at it as work. I can be at home in the shop working at my leisure , chit chatting with the family, babysitting the bbq, or watching the tv at the same time. It gives me something productive to do/look forward to rather than idle time or less than productive time
I wanted to learn as much as possible in the process so that I could understand and assess troubles in the future.
I did save significant money in the process, I paid less than 7k for 60kwh of battery, but prices on prebuilts keep coming down. In the future I will just buy user serviceable prebuilt batteries.
In reality, I don’t look at it as work. I can be at home in the shop working at my leisure , chit chatting with the family, babysitting the bbq, or watching the tv at the same time. It gives me something productive to do/look forward to rather than idle time or less than productive time
I wanted to learn as much as possible in the process so that I could understand and assess troubles in the future.
I did save significant money in the process, I paid less than 7k for 60kwh of battery, but prices on prebuilts keep coming down. In the future I will just buy user serviceable prebuilt batteries.
ScropusGobbleBottom
Corn Pop was a bad dude.
LOVE this attitude. I share it with you. I love learning at my own pace with a nice payoff at the end.
Ampster
Renewable Energy Hobbyist
I spent a lot of time putting together my pack at two homes. First it was 32 LF280 cells at one home. Then after I purchased another 16 cells we decided to move to another home. I had not pulled a permit on that system so I disconnected the inverter and moved the cells to the new home. After pulling a permit for a 8kW grid tie solar system and a new main service panel two years ago I installed the inverter and the pack of 48 cells. This year I resolved to get the SolArk system permitted as well. The only practical way to do that was to use UL listed batteries and so I sold my LF280 pack and installed four Pytes V5 rack mount batteries in an external enclosure. I am done with the install and cleaning up that part of the garage so as not to distract the inspector and plan on calling for inspection next week. My motivation was not the time or the cost but the desire to finally have a fully permitted system.
I wonder, is there a way to get a DIY system inspected in some fashion so that it can be permitted? Ultimately, the prebuilts use the same cells, they just build it to a certain minimum standard, apply for UL listing, get it approved and then it's listed. Much how an inspection checks install, could something like that be done for DIY batteries? For example, I'm likely gonna build a battery with a case from China, where everything is made anyway. I will probably go above and beyond the minimum required, like install better bus bars, cabling, and internal-to-the-pack fuses which are not part of the standard build blueprint. It'd be a shame not to be able to get it permitted.
zanydroid
Solar Wizard
Nope, not allowed currently. They don't even allow you to build your own UL9540 system out of UL1973 batteries.
They won't even send an inspector out to retroactively bless a factory-built unit sold prior to completing UL testing, without a massive ceremony (if it's not impossible).
If you were a big commercial or industrial site you could go an alternate route involving a team of engineers to certify the bespoke ESS that you are building
ScropusGobbleBottom
Corn Pop was a bad dude.
THIS is utter BS.. Fricken gestapo.
Drunk Engineer
New Member
I wonder whether this built-in extinguisher is actually effective for a battery fire, or just a costly gimmick?
Dave911
Solar Enthusiast
I think Will needs to "fire test" one of his batteries.
. I suspect its a gimmick.in the UK, the difference between a delivery kit of 15kWh and a pre-built battery with warranty is about $350-400, which is about 20% - for me, not worth it, but if I were doing four or more of them, a definite saving.....
zanydroid
Solar Wizard
That’s the rules set by NRTLs that have come up in threads, delegated to them by the regulations.
zanydroid
Solar Wizard
I’m guessing it’s part of the kitchen sink thrown at the design until the NRTL team reviewing the battery is willing to pass it
Dave911
Solar Enthusiast
OR did EG4 believe an extinguisher was required due to a real possibility of a battery fire?
Dave911
Solar Enthusiast
Is that an assembled and lab tested and approved battery? Or just a shop assembling batteries?
That doesn't seem bad at all, which ~15kWh prebuilt have you priced that competes with a delivery kit for only that much more?
Fogstar - https://www.fogstar.co.uk/collectio...e/products/fogstar-energy-15-5kwh-48v-battery
If installed the VAT is 0% not 20% at the moment with a government initiative. From the website:
The Fogstar Energy 15.5kWh Battery, meticulously engineered for UK conditions, provides an unparalleled combination of cutting-edge technology and exceptional durability.
This 15.5kWh home battery boasts numerous advanced features, including;
If installed the VAT is 0% not 20% at the moment with a government initiative. From the website:
The Fogstar Energy 15.5kWh Battery, meticulously engineered for UK conditions, provides an unparalleled combination of cutting-edge technology and exceptional durability.
This 15.5kWh home battery boasts numerous advanced features, including;
- Intelligent Heating System: Our batteries automatically activate their heating function when temperatures drop below 5°C, ensuring optimal performance even in frigid environments of -20°C.
- Plug-and-Play Inverter Compatibility: The PACE Battery Management System (BMS) seamlessly integrates with a wide range of popular inverters, including (but not limited to) Victron, Pylontech, Growatt,Sofar, Solis, and Goodwe. Changing the inverter protocol doesn't involve any complex software downloads, you can change it simply by navigating the LCD Touchscreen.
- Unwavering Confidence in Quality: We stand behind the exceptional design and construction of our batteries, offering an industry-leading 8-year warranty and a 15 year shelf-life. This testament to our craftsmanship reflects our commitment to delivering products that last.
- Intuitive Touchscreen Interface: The 4.3-inch TFT LCD touchscreen provides a user-friendly interface for monitoring system status and adjusting inverter protocols.
- Energy-Efficient Sleep Mode: When not in use, the touchscreen automatically enters sleep mode, conserving precious energy while ensuring instant access to detailed system information upon activation.
- Premium Grade A EVE Cells: The Fogstar Energy 15.5kWh Battery utilizes 16 premium LF304 Grade A EVE cells, renowned for their exceptional lifespan of 3500 cycles at a discharge rate of 200A per cycle.
- Active Balancing: Contains a 2A JK Active Balancer to ensure seamless cell balancing during the charging process.
Dave911
Solar Enthusiast
Just over $200 per kwhr in US dollars is not bad considering the packaging, eve cells, warranty and screen. Is there anything comparable in the US?
I don't know, sorry. They are relatively small so may reply helpfully if you emailed them.....
Similar threads
