diy solar

diy solar

1088Ah 32 cell LiFePO4 Lishen 24-Volt 8S4P build, actually 4P8S as parallel connections are 1st.

i re-oriented the cell pack to not be such a long battery bank but rather a square battery bank. i will re-orientate the graph paper photo to make it easier 32 cell 24 volt 8S4P 272Ah Lishen design july 6th 2021.jpgto read.
 
Fingers Crossed that you are not trying this with Bulk Commodity cells.
Lessons Learned dept about those in parallel. Does not matter brand or AH capacity.
Let us know how it goes.
 
got the new 15,000 watt 24-volt inverter set up and running at low watts on another LiFePO4 battery yesterday so I will be able to test it out on the bigger battery. everything is going slow as so much to do in the summertime.
had to hydraulically crimp some 4/0 cables from the inverter to the heavy duty bus bar.. all shrink-wrapped with the adhesive lined red and black shrink wrap for color-coding ease. and tightened down. I plan to hook it into a new 100 amp breaker box for the ac side of things. slow but sure, maybe more slow than sure.
right now the slow part is making the busbars for the 32 cell LiFeP04 battery build. among other demands from the family.
more later! ?
I taped all exposed connections on the inverter terminal for safety.
a reminder as one time i arced another LiFePO4 battery >>>> safety 1st around the arc welder capability of LIFePO4.?
 
Pssst... ever see what happens to gold wedding ring with a big DC arc ?
hint, you don't wanna, not ever. Necklaces also a nasty one too.
 
Today I ordered 64 busbars from China on Aliexpress. after researching all methods and costs to connect the 32 cells (Lishen 272Ah prismatic aluminum cased cells) in a 4P then into 8S configuration. The LifePO4 cells must be connected in parallel 1st, then connected in series. The cost for 64 tin-plated solid copper bus bars is $125.07 (shipped to me including tax and shipping). i looked at 2/0 cable and lugs but was easily running into 300-400 dollar range plus hours and hours of my time and labor so went the prefab route from the Chinese seller on aliexpress. I will still have to get 25 more longer bus bars or cables for the series connections. so probably another 100 or so dollars for those. definitely not a nickel and dime project. I will ultimately hook them up to an Electrodacus SBMS0.
I definitely do not wear metal jewelry around 500 to 1000 amp LiFePO4 battery banks. ?
I will likely be building a larger solar power shed or an addition to the one I Am setting this up in.
Slow but sure>>> maybe more slow than sure!
 
Haste Makes Waste is VERY TRUE ! never rush into things, especially if it's not your comfort zone and take your time to do it right the first time.
TIP: If the busbars you ordered have one round & one elliptical hole and you are doubling them up, put them in opposites. 1 round & one elliptical on the same hole.
 
more later I am in the process of assembling a 32 cell 24volt Lishen 272 Ah battery bank. I have 8 groups of 4 272Ah cells in parallel and I am awaiting the 2/0 copper cable and .25 inch tinned copper lugs to make the parallel to series battery interconnects. It will be 272 x4 = 1088 Ah potential at 24 volt nominal so 3.2 volts x 32 272Ah cells = 27852.8 Wh capacity @ 1088 Ah potential. likely will only use 200 amps or less ---- that is the goal, but will have more reserve capacity. 3.2volts x 8cells = 25.6 nominal volts but that is the low end, it will likely be at 3.4 to 3.55 so more likely (3.4x 8= 27.2 to 3.55x8 = 28.4 volts) 27.2 to 28.4 volts. my Electrodacus SBMS0 stops charging from the solar panel array at 3.55 volts. the Electrodacus SBMS0 controls the Electrodacus DSSR20's which are the solar charge controllers. the Electrodacus SBMS0 balances the cells when they are charging. ?
the new insulated bus bars I received from China are good for the paralleling but not long enough for the cell interconnects so have to make them out of 2/0 cable and lugs with .25 inch holes for the Lishen battery build the slow hard way. (28 to be made at about 6 inches each).
Just a small update -- had to cut down 2 big cedar trees to get better sun for the increasing solar array! ??
 
I ordered 80 cable lugs for $107.00 from Amazon. they are tinned copper lugs with a .25 inch hole for the M6 studs on the Lishen 272Ah cells. I also ordered 2/0 copper cable 20 feet (of red) for $64.69 from Amazon. the price per unit and price per foot was better on Amazon than what I found on eBay. I need to make 28 interconnects so I needed 56 lugs then I would also make 8 more cables to connect out of the positive and negative so in total, i needed 64 (possibly 72) lugs for the 2/0 battery cable interconnects for the serial connections. each serial interconnect will be approximately 6 inches so I have a little extra 2/0 cable and a few extra lugs. for slight changes.
i plan to clamp the hydraulic crimper in a vise to give me a bit more control when crimping the cables. I saw someone else do this on YouTube and it will help a lot. seems you never have enough hands. ?
so the battery cable interconnect will cost $171.69 for 36 DIY 2/0 cables with hydraulic crimp-on lugs. plus I will use heat shrink to protect the ends so a bit more for that. all other methods would cost a lot more; at least in my search finds.
always best to order extra as you can't stretch the wire.
I have no cable stretcher and also do not own a board stretcher. ??
 
Today I ordered 64 busbars from China on Aliexpress. after researching all methods and costs to connect the 32 cells (Lishen 272Ah prismatic aluminum cased cells) in a 4P then into 8S configuration. The LifePO4 cells must be connected in parallel 1st, then connected in series. The cost for 64 tin-plated solid copper bus bars is $125.07 (shipped to me including tax and shipping). i looked at 2/0 cable and lugs but was easily running into 300-400 dollar range plus hours and hours of my time and labor so went the prefab route from the Chinese seller on aliexpress. I will still have to get 25 more longer bus bars or cables for the series connections. so probably another 100 or so dollars for those. definitely not a nickel and dime project. I will ultimately hook them up to an Electrodacus SBMS0.
I definitely do not wear metal jewelry around 500 to 1000 amp LiFePO4 battery banks. ?
I will likely be building a larger solar power shed or an addition to the one I Am setting this up in.
Slow but sure>>> maybe more slow than sure!
do you have a link to the chinese store you bought those busbars at ?
 
I am using the Riden 6012 and Riden 6018 battery chargers to charge the 4 cells in parallel. the charge has been slow on 1 set of 4 paralleled cells, but is near completion now. I am bringing them all up to 3.40 volts at the moment. this is being done all off-grid with my 8000 watt 24-volt inverter (not using anywhere near that many watts). it has other small loads running constantly 24 hours a day. the Ridens only add another small load maybe 100 to 200 watts or so. that is why it is a bit slow. but not a problem as I await the cable and lugs to arrive to make up the series interconnects. the problems I have encountered with the two other 16 cell 24-volt battery builds usually was found to be a connection not tight enough. just employing a bit of caution not to overtighten the studs and flange nuts on the M6 battery connections, as I do not want to strip them as some other people have done. ?
another issue I have run into is trying to keep the temperature in the solar power shed down. when I have 3 24-volt inverters running the heat seems to creep up a bit. I cool it off at night as best I can. originally I was trying to keep the LiFePo4 batteries from freezing, but in the summer heat, I am trying to keep it all from getting too hot. ?
 
do you have a link to the chinese store you bought those busbars at ?
alliexpress >>> the store vendor was HanHang LiFePO4 Battery Store

Pure Copper Nickel Plate Busbar For Lithium 3.2V Lifepo4 Battery Cell Connector 272Ah 280Ah 300Ah 310Ah​

I bought 64 of these bus bars. they are thicker than the ones I received with my 1st set of 32 Lishen cells,
and they have the shrink wrap insulation already applied..
the 16 piece sets are the best buy. scroll down and you will find them.
64 nickel plate copper busbars cost $125.07 dollars with free shipping. to the USA.
I like them!!!! ?
 
I ordered a Delta 24volt 5500rpm 120mm fan yesterday from Aliexpress for $13.57 including shipping and tax. I think I will add this onto the transformer box to aid the cooling a bit. 120*120*38; I think it is 1.2 amps. model number FFB1224 12038 24 v 2.2 5500 RPM from SENSDA Electronics Store.
I also ordered 50 pieces of 25mm long M6 set screws (grub Screws) for the 32 cell Lishen battery build these were only $3.70 for 50 pieces including shipping. This will make it easier to attach the Electrodacus SBMS0 sense wires and tinned copper lugs on the new Lishen 32 cell battery build from another vendor on Aliexpress.
Time to make some coffee! using the solar power saved in the LipO4 battery!!!
the 2/0 tinned copper lugs arrived yesterday, the 2/0 cable should be here today.
I ordered another Electrodacus SBMS0 (from Canada) at Electrodacus.com specifically for this new battery build it should be here in about 10 days or so. more later. I will have to wait longer for the Aliexpress China order (grub screws and delta fan) but I have enough pieces to assemble and test out the larger battery.
future builds will need other parts. but these builds are currently 24-volt LiFePO4 builds with 24-volt inverters. ? I have 2 other Electrodacus builds up and running on 250-Watt 60 cell solar panels charging 16 cell 24-volt LiFePO4 (2P8S) battery builds and they are hooked up to 6000 and 8000-watt inverters running 24/7.
This NEW 32 cell Lishen 272 Ah cells are connected in parallel 1st in groups of 4 >>>> this gives each group 1088Ah at 3.2 nominal volts. then each group of 4 cells will be connected in series to get the 24-volt battery (4P8S configuration) the correct way is to hook the cells in parallel 1st. the series connection will have the higher amperage (current flow) at higher voltage so I am using 2/0 copper cable for these (4 cell group) interconnects with hydraulically crimped lugs.. ?? This battery will be 3.2V 272Ah Lishen cells (32of them) wired 4P8S so it will be 1088Ah and 3.2X=25.6 volts nominal.
25.6 volts X 1088 Ah = 27,852.8 Watt-hour potential capacity or 27.852 kWh.
The 272 Ah Lishen cells are said to do 285 or 290 Ah. But I do not need them to do that much and the normal running voltage of my 24-volt batteries is more like 27.2 at 3.4 volts per cell when charged by the solar panels up to 28.4 volts if every cell is at 3.55 volts.
The Electrodacus SBMS0 stops the solar charging at 3.55 volts to prevent overcharging the LiFePO4 battery bank. The Electrodacus SBMS0 controls the Electrodacus DSSR20's to prevent overcharging. I have 2 60 cell 250-Watt solar panels hooked in parallel to each Electrodacus DSSR20 and they are capable of up to 20 amps of solar charging each. The Electrodacus DSSR20 solar charge controller is a solid-state relay and is not a PWM or MPPT type of solar charge controller.
 
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I ordered these on Aliexprees 50 of them for $3.70 including tax and delivery

Hexagon Hex Socket Set Screw Flat Point Allen Head Grub Screw M2 M2.5 M3 M4 M5 M6 M8 M10 M12 Stainless Steel Headless Set Screw​

Price:
US $3.70 / piece
Size:
  • M6 50pcs
Length:
  • 25mm
 
Here is a pic of the $5.00 drill press garage sale buy and my $60.00 hydraulic crimper.

Ihave used the 16-ton hydraulic crimper for many large gauge cables but did buy a smaller crimper for some small gauge wire hydraulic crimping also.

the old man selling the drill press vise already had it mounted on a board with a couple wood runners to mount on his drill press, so it makes a good stable base as well. Never have enough hands when making up cables it seems.

20210826_121419.jpg
 
28 interconnects crimped using 2/0 copper welding cable. they are 2.75 inches of cable with a double hydraulic crimp on each lug. the tinned copper lugs have a .25 inch hole for the m6 grub screws on the 272Ah Lishen cells.
each one measures 4.75 inches center of lug hole to center of the lug hole.
shrink wrap will be here tomorrow. so I will make them with less exposed copper lugs. and sealed with adhesive-lined shrink wrap.
2.75 inches x 28 = 68.75 inches of 2/0 royal excelene welding cable.
20 feet cost about 64 dollars of the 2/0 welding cable.
I will eventually get the costs in an excel table.
the hydraulic crimper worked great.
I used the Jokari to strip the cable before crimping.
a small cable cutter to cut the cable into lengths two at a time. that way i could walk away as needed for other work.
each 2/0 cable interconnect has a 200 amp capacity rating.
 

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2/0 tinned copper lugs I like them!
trying to get the link address:
keeps showing my order details --- search for them you will find them! Sorry
Color:2/0 AWG - 1/4''Ring
sold by supercloud on Amazon

10 pieces for $12.99 with free delivery on Amazon prime. I ordered 8 packages of 10 so I had plenty. $107.00 total including tax!
these are the tinned copper lugs for the 2/0 cable interconnects.
the lugs have a funnel shape to aid the cable insertion which helps as the cable has a lot of strands and you want to get them all into the lugs.
I crimped each lug 2 times: the first crimp farthest from the lugs' end with the hole and the second crimp slightly closer to the lugs' end with the hole. this way the cable does not get pushed out the lug when crimping. one should apply a small force pushing the cable into the lug while crimping and make sure the lugs are in the right orientation especially important when crimping the lug on the other end of the cable!
 
Here is a pic of the heat shrink tubing I bought 82 feet roll on Amazon at the XHF store for $48.06 including tax.
this is way more than I needed but will use eventually it.
A 2 to 1 shrink tube adhesive lined; good for 2/0 cable. they sell other sizes and lengths! ?
I found that the heat gun got hot and used a pair of electricians pliers to hold on to the lug while heat shrinking them; my pinkies said thank
you.! ??20210901_165613.jpg
 
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I may start the series connections tomorrow; I want to make a slightly larger base to place all 32 Lishen 272Ah cells on to allow room for the compression jig and their threaded rods. amongst the other things on the honey-do list! ?
 
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