diy solar

diy solar

Help us design a rack-mounted system for the UK

Ben, i think the issue wont just be with the shipping, when they get to their destination, how will someone be able to pick them up and move them? However if you also designed a self build pack of four boxes of cells and one box containing the rack mount (or wall mount?) then it becomes more viable
Disagree. They would only be around 100kg, which is manageable with suitable handles or points to attach loops. 2 good blokes could stack them four high pretty easily. You're not going to be lifting through a loft hatch though.
 
Disagree. They would only be around 100kg, which is manageable with suitable handles or points to attach loops. 2 good blokes could stack them four high pretty easily. You're not going to be lifting through a loft hatch though.
thats if youve got two good blokes ....... i am talking about the average bloke, on his own. i am surprised that you would suggest discounting the idea though, it seems to make business sense to me that offering 'options' would be the better way forward.
my suggestion used the word 'also', meaning another option could be offered aswell !

as for stacking them four high, at 4 x 13.4kw - thats one hell of a 'battery wall' and i wouldnt have thought there was a massive market for that size of installation. i suppose thats why most systems are offered as modules of 4.5kw or thereabouts?

i am far from being experienced in battery storage systems and i might be talking a right load of bollox ......LOL
 
A premade 48V system using Eve 280Ah/Eve 304 is the next project. We're also looking at stocking a seplos system for those who like DIY. It's finding a UK carrier that will pallet ship for a reasonable price.

Biased suggestions:
1) Enable an option for Seplos (for those who don't want active balancing/don't want to tinker) or JKBMS (for those that do want active balancing & who have experience in modding stuff (<= all mods void warranty etc)).

2) DIY Kit option in addition to Done-For-You with a check-box that only allows person to purchase with something along the lines of:
"I understand that this option is for advanced users only, and I will not receive any direct support from Fogstar, apart from any provided instructions/documentation/videos"
...might mean you pick up an additional 20% of sales for people who like modding stuff (I guess there just might be a few of them here on the Forum :giggle:)

Pros of Seplos: Out of the box works as a Pylontech substitute in terms of CANBUS comms
Pros of JKBMS: Active balancing (which has definitely been useful, even with Grade A cells) & integration with projects such as https://diysolarforum.com/threads/d...hunt-to-inverter-integration-solis-etc.44750/ )

EDIT: Here's what I mean about the active balancing feature of the JKBMS (admittedly, these are good quality Prismatics, so maybe they'd be that close anyway) - all cells within 1milliVolt of each other after an overnight charge that finished 2 hours ago:

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DC rated breaker added. Screen finally done.

Terminals took a fair bit of decision. We wanted customers to be able to make their own cables, or atleast purchase them/customize the lengths. Not a fan of these new push fit terminals that are impossible to make - but they are really safe. So we went with a screw terminal for ring connectors. We then added some covers, to stop little fingers from getting in there incase mum or dad leave the cabinet unlocked.
 

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Onto some boring stuff now.

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Paying programmers to translate the user interface, if plugged into PC to try and make a more friendly experience.

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Designing rack cabinet. Couldn't find a premade one that had integrated busbars and would take the weight. Integrated bus bars, alot of copper, but the best solution we think! Also means that we can can have mesh over the screens, and some other custom stuff to improve designs.
 
Looking great, i like the "We have Hyperdrive Captain" message on the LCD. Not being overly familiar with server rack batteries, do they have temperature control fans like an inverter does if a certain temperature is reached?
 
Looking great, i like the "We have Hyperdrive Captain" message on the LCD. Not being overly familiar with server rack batteries, do they have temperature control fans like an inverter does if a certain temperature is reached?
They shouldn't get overly hot in this country, so I doubt it... but they have heaters for when it gets too cold, which is a big + :)
 
Come on Ben, get your finger and get them finished lol, Becs is getting impatient to sell them!
Any idea of price yet, are you going to sell just the cases for those of us that have already bought cells from you ??
 
Come on Ben, get your finger and get them finished lol, Becs is getting impatient to sell them!
Any idea of price yet, are you going to sell just the cases for those of us that have already bought cells from you ??
Probably £17,000 each with the amount of things I keep adding to them . But they will look nice in my garage!! Just joking! We will make them the cheapest £/kwh available currently for a warrantied option. I kind of make things that I would want, and hope other people want them too lol

DIY kits are next for racks, DIY boxes for the 280Ah cells (similar to seplos with interchangeable BMS) along with commercial versions pre-built.

I've also thought about maybe doing a DIY powerwall with the 280, so similar to the seplos, but cells are stacked instead. Just to make the footprint a little smaller. Haven't really hashed out the details or how to do it yet. I was thinking 4 x 280, side by side, but 4 rows, one on top of one another.
 
Probably £17,000 each with the amount of things I keep adding to them . But they will look nice in my garage!! Just joking! We will make them the cheapest £/kwh available currently for a warrantied option. I kind of make things that I would want, and hope other people want them too lol

DIY kits are next for racks, DIY boxes for the 280Ah cells (similar to seplos with interchangeable BMS) along with commercial versions pre-built.

I've also thought about maybe doing a DIY powerwall with the 280, so similar to the seplos, but cells are stacked instead. Just to make the footprint a little smaller. Haven't really hashed out the details or how to do it yet. I was thinking 4 x 280, side by side, but 4 rows, one on top of one another.
Looks very interesting. Have you thought of making modular stackable free-standing legs so they can be stacked without the need for cabinet? I can send an example. This would reduce the price point.

Whats the pricepoint you are aiming at commercially. There could be an opportunity here.
 
Onto some boring stuff now.

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Paying programmers to translate the user interface, if plugged into PC to try and make a more friendly experience.

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Designing rack cabinet. Couldn't find a premade one that had integrated busbars and would take the weight. Integrated bus bars, alot of copper, but the best solution we think! Also means that we can can have mesh over the screens, and some other custom stuff to improve designs.
looking good ben..
one hope though..
seen so many prebuild batteries that are shipped by suppliers / manufactorers with unbalanced cells that causes users issue a few months in .
i hope fogstar will do it different.
i realize that may take more time for assembly, but it would save your users ( and ultimately fogstar) loads of headaches and frustration
 
Any new info? Been looking for something like this. Found only seplos, but they are a bit pricey, asking $600 for case with bms.
 
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