Battery Enclosure for LIFEPO4 - powerBASKET?

[@AveRage_Joe]

Looks Amazing Man!!!💥

[@StuartPittaway]

Thanks!!

[@OffGridGarageAustralia]

A powerBASKET... haven't seen this before🤣

[@wayne8113]

Thanks Stuart, have been watching Andy & Joe as well, getting ideas from you all, I do like your folded and Lazar cut enclosures.(I don't want mine to come off the wall to far ether) Keep up the great work 👍

[@StuartPittaway]

Thanks for watching.

[@MiniLuv-1984]

That looks surprisingly like how I made mine...and for pretty much the same reasons. Looking forward to the next video Stuart.

[@StuartPittaway]

Nice one

[@KoRWraith]

Hi Stuart, How much did the laser cutting company charge to produce your design? Also, you mentioned the Seplos Mason comes with a BMS which you wouldn't use, is there a particular concern with regards to the included BMS?

[@StuartPittaway]

Laser cut enclosure was less than £200, the BMS with the Seplos is unsurprisingly the Seplos BMS !

[@misterb5216]

@@StuartPittaway are you using a Seplos BMS then please? is that so it can communicate with the Sofar inverter? do any other BMS's work with the Sofar inverter?

[@StuartPittaway]

I'm using my own DIYBMS system in the battery build

[@MagicGumable]

Very nice design! I would personally add some sort of caster wheels as it already looks very rugged and heavy without any lifepo4 :D

[@StuartPittaway]

Cool idea!

[@Thunderst0rn]

Hi Stuard, nice design and implementation. If you would redesign the battery compression part, how would you alter the current design?

[@StuartPittaway]

The existing design does work well, but its probably over engineered, the unistrut rails I've used are overly heavy, and its probably just as easy to use threaded rods to achieve the same thing. I would also now design the enclosure as rack mount style, probably floor mounted.

[@GalvayraPHX]

There's a lot of thermal insulation in there. Aren't you worried about the pack overheating in summer when charging/discharging at high currents?

[@StuartPittaway]

The inverter is 3kW max - which is 60amps - so each cell is charging/discharging at less than 4amps each. The cells are rated at 0.5C (140amp) maximum, so its a tiny amount compared to that. There is still potential for over heating - but the BMS will tell me that and stop charging. From memory 55oC is the highest temperature the cells are rated to.

[@GalvayraPHX]

@@StuartPittaway Thanks for answering :) That is indeed a small amount, however: * Are the cells all going to be in parallel? If so, can you guarantee the current will split evenly? I don't expect there to be large differences ( unless some failure occurs) but there will certainly be some which will lead to some cells having a higher temp. * I don't know how high the ambient temp goes to in your climate/garage in summer, but considering how little heat the box will loose, it can accumulate. That depends on how hard the system will cycle, so basically on the system load and solar power input. And in summer you have both a high ambient temp and a lot of solar power coming in. The BMS protection will shut it down on overheat, but that would be a loss - if the box had a fan mounted, that could help with overheating a lot. And you could cover the vents during winter. Also, what does happen at the end of charge when say, some cells are "full" and others are still charging? I understand the BMS will be discharging the full ones to balance them, but does it do it at the full charge current? Now that I think of it, if they were all in parallel is it even possible to balance individual cells?

[@StuartPittaway]

The cells won't be in parallel - its a 16S series string, giving 16x3.2V nominal voltage (51.2V). You are correct, the current won't be equal across all cells and depends on the internal resistance, hopefully that's very similar across the cells. Agree with the fan idea - I may just remove the insulation in the summer months, if it becomes a problem. The max temp I've recorded this year was 34oC in the garage - so the 55oC max is a possibility. The BMS can control the inverter/charger using CANBUS, so it can dynamically lower the charge rate into the cells if it needs to, based on balance/temperature or state of charge.

[@GalvayraPHX]

@@StuartPittaway If it's a series string, all the cells should have the same current...ish. So...full 60A over each cell, I think? You'll be able to test it as soon as it's all put together though, no need to wait for summer. But I'm looking forward to a follow-up video next September about how it went :)

[@StuartPittaway]

@@GalvayraPHX You are correct, I'm mixing up my Volts and Amps again !!

[@gigaz2]

what battery connectors are those? Great build, will the front panel be visible when mounted on the wall?

[@StuartPittaway]

Yes the front panel will be visible. These are the connector posts - www.aliexpress.com/item/1005003993706972.html?spm=a2g0o.order_list.0.0.3aea18025OXM3Y

[@CollinBaillie]

If you're a fan of Modded Minecraft, you could use BattPack.... Or change it a bit.. the BattStack? Nice enclosure.

[@StuartPittaway]

I know its a crap name :-)

[@Truevideoz]

Is it possible to reorder the enclosure box which you made from the same company? Is there any diagrams or any details which we can use to get it made instead of re designing? Can you give the laser cutting company ?It would be good if you create a video with prices of all the items and the place where we can procure it at the best price and alternatives if its there and Can you supply the bms? We can get the daly or JR or so from the market but if you are providing something for 16s battery that would be great

[@StuartPittaway]

I've not published the files I made for the box. I used a local laser cutting shop to cut and fold the steel.

[@ndudman8]

I've had mine commissioned for a few months, but I need to make a simular box. What where those connectors you used ? Any links you could share ? Ah found it on aliexpress "250A Through-wall Terminal New Energy Energy Storage Lithium Battery Positive And Negative Copper Terminal Connector", now just looking for the other switches :)

[@StuartPittaway]

The MCB's I used are from ProJoy - quite hard to find/order.

[@georgef7754]

I think Paul Kennett may have a claim to powershelf.

[@StuartPittaway]

Could well be the first!

[@aragorn084]

Is the plan to integrate the ME3000SP with DIYBMS?

[@StuartPittaway]

Yes. I've already got the code working for pylontech battery emulation, it's on a GitHub branch.

[@Reebcor]

​@@StuartPittawaycan you tell me how to do this? I need to get this code and how to install it thanks

[@santosvella]

Very cool Stuart. Why would you need compression in the first place? I'm not familiar with building batteries. Wouldn't the nice case hold things okay?

[@StuartPittaway]

LIFEPO4 cells swell up when charging and this can lead to a shorter life. Its not critical to compress them, but hopefully gives them a few years more life.

[@markseamans4682]

I am no expert by all means, but the way I understand it, is if the batteries will be light use, then there is really no need for compression. If you will be discharging/charging fast, then it's a good idea. Also, if your batteries will be seeing vibration (ie: in an RV or such) it's a good idea to compress to ensure the bus bars don't tweak the terminals too much.

[@StuartPittaway]

@@markseamans4682 I'd agree, the cells are only lightly compressed to hold them in place. It will also stop them moving/stretching the connecting bars.

[@markseamans4682]

@@StuartPittaway For my RV build with the 304Ah cells (48v) I'm planning to use 2/0 with some well crimped lugs to allow for a bit more vibration. I'll use some MG Chem 847 in the lugs and assembly to help prevent resistance. Naturally, I'll pull out my ohm meter and do some tests first. I also picked up a internal resistance meter for LI batteries. Hopefully it can shine a brighter light on the build.

[@wahabhabeeb8614]

PowerBox is more appropriate name for your design.

[@StuartPittaway]

Good idea!!