DIY BYD Blade Battery Pack 7.066 kWh for $1,220 ??

[iamrich]

How does shipping look now for 3 packs of 21.198 kWh ? Total below

Cost / Price

3 x 16S1P BYD Blade Battery Pack with screws and bus bars: $2,016
3 x BMS for 16S1P: $330

Shipping from ShenZhen China to Miami Florida: $638

Total: $2,984

In reality, it is all what you are willing to pay. Prismatic cells are right around $166 per kwh delivered (+/- $20). Figure the BMS is going to be the same for either, so taking your numbers above, you are looking at $112 per kwh delivered for the cells (if I did the math correctly). I would consider that a great deal assuming these are genuine BYD cells, and they make it across the ocean. You will have additional costs putting these together (banding/compression, wiring, some kind of enclosure, etc.), but I think the price is very tempting.

The current plug and play go to battery is the EG4 5.12kwh (48v/100ah) and that is right at $300 per kwh. It comes ready to use (BMS, breaker, load resistor, etc.).

 

[BrickedKeyboard]

Note that you very likely do not need cell compression with these. They won't have them mounted in an EV how could they? The blades are attached on edge, look at the videos. Nothing compresses them.

I think you could build a lazy blade battery by just laying them flat on a cement board. Zip tie em down.

 

[BrickedKeyboard]

Or just build a footing out of wood or aluminum rail and 90 degree connectors. Slide the 16 bladed Into the footing, stand them up vertically. Straps or something to hold the bundle to a cement board.

Maybe just a few cement blocks will do.

Then all the connections you make at the top to the BMS and using 100amp rated cable with crimped lugs. Mount the BMS on the same cement board. Then a mounted breaker and a couple of mounted 48v bus bars that you connect your inverters to.

I think it would work though these blades are crap. The vehicle grade cells are 160Ah or better. Should probably wait til you can buy vehicle grade cells or wall mount packaged batteries that use them.

 

[luisenriquereyes]

...Should probably wait til you can buy vehicle grade cells or wall mount packaged batteries that use them.

Yes would like to get a comparison of the vehicle grade cells.

Wall mount packaged batteries seem to be available from these two companies:

Linkage Electronics https://linkage-battery.com/

Videos of their pack:

and Raymond Shen with titanpower-battery.com

Raymond Shen

diysolarforum.com

 

[BrickedKeyboard]

Yes would like to get a comparison of the vehicle grade cells.

Wall mount packaged batteries seem to be available from these two companies:

Linkage Electronics https://linkage-battery.com/

Videos of their pack:

and Raymond Shen with titanpower-battery.com

Raymond Shen

diysolarforum.com

View attachment 78728
View attachment 78731

Thank you for this.

https://electricvehicleweb.com/byd-blade-shaped-battery-breakthrough-battery-safety/ per the official specs, the vehicle grade cells are supposed to store 202 Ah! This looks like the same part number as the dimensions are the same as these shady "120-138Ah" cells.

This isn't grade "B" cells this is grade "F we stole it from the reject bin" cells. Not a good move, there must be massive internal faults for a 202Ah cell to test out only at 138, I would not expect it to last 10+ years, these things are industrial waste.

 

[BrickedKeyboard]

What it does show is that these things are going to be super cheap soon enough. What I read is that BYD's price to EV manufacturers is $65/kWh. Packaged batteries for $100-$150 a kWh will be compellingly good and this is approaching the point that it will be cheaper for just about everyone to have home storage batteries.

If the battery lasts for 15 years and you get a net utilization of half it's capacity (meaning plenty of days you have too much solar and don't drain your batteries flat by morning), then at $100/kWh/(365*0.5*15) = 3.65 cents a kWh. Even in Texas, where power was cheap, rates are going to have to rise a lot (to pay for the bills incurred by the power shortage during the freeze) and this is probably worth it.

A bigger problem is packaging. The battery and inverter and enclosure for it all and a tap that goes directly between the meter and the meter socket are what you need to really make this super cheap. Then an electrician needs to do all of 20 minutes of work to install one electrically, and a couple hours to mount the enclosure.

 

[eXodus]

Watt-hours: 7.066 kWh
Weight: 42.08 Kg ( 93 lbs )

Woa this things are light. I just got 5kwh with 98 lbs.

Only about 15lbs / kwh. While my other pack is almost 20lbs/ kwh.

You could build a 100kwh pack as less then 1500lbs.

What it does show is that these things are going to be super cheap soon enough. What I read is that BYD's price to EV manufacturers is $65/kWh. Packaged batteries for $100-$150 a kWh will be compellingly good and this is approaching the point that it will be cheaper for just about everyone to have home storage batteries.

My break even point for Solar Storage is close to $150/kwh, since I live in a sunny climate with low energy cost.
For less sunny places you need more battery and hence they need to be cheaper.

 

[BrickedKeyboard]

My break even point for Solar Storage is close to $150/kwh, since I live in a sunny climate with low energy cost.
For less sunny places you need more battery and hence they need to be cheaper.

Do you? Please think about it for a moment.
Climate A: 5 sun-hours per day, every day
Climate B: 2.5 sun-hours per day, every day

Both climate A and B you have the same energy demand. (hypothetical)

Actually the battery size you need in both cases is identical : you need, in this case where you get the same predictable sunlight each day, a battery bank that stores approximately 24 hours of usage. You need 2x the solar array in climate B.

The actual reason you need big batteries is if A or B have periods of sunny day, cloudy day, sunny day, cloudy day, etc. If the cold climate has a long winter period of no sun a bigger battery isn't very useful, since it still runs flat for any reasonable period. (like in Alaska)

Anyways I think you'd need to run a python script on PVwatts data for your zip code for day by day sun, factoring in your battery costs and local power costs and panel costs. Maybe I'll write one it's not very hard.

Can you help me out : what is a good ballpark number for PV panel mounting costs? Signature solar has assorted PV panels for around 50 cents a watt, but I don't really have a good idea on what the mounting hardware ends up being. Obviously will's solution of laying them on the ground is almost free (those bricks he uses have a minimal cost)

 

[eXodus]

Do you? Please think about it for a moment.
Climate A: 5 sun-hours per day, every day
Climate B: 2.5 sun-hours per day, every day

You average values - for your scenario - you are correct. But the real world doesn't run in averages.

But usually - it's a lot more intermitted. I get 10-12 hours every day - and sometimes no sun for 3 days.
In a less sunny climate - you get 5 hours every day and no sun for 5-10 days at a row.

The more intermittent sun you have - to more battery capacity you need.

 

[BrickedKeyboard]

You average values - for your scenario - you are correct. But the real world doesn't run in averages.

But usually - it's a lot more intermitted. I get 10-12 hours every day - and sometimes no sun for 3 days.
In a less sunny climate - you get 5 hours every day and no sun for 5-10 days at a row.

The more intermittent sun you have - to more battery capacity you need.

Last part I agree with. Have to check the relative intermittency on PVwatts to determine this.

 

[polar ape]

Thank you for this.

https://electricvehicleweb.com/byd-blade-shaped-battery-breakthrough-battery-safety/ per the official specs, the vehicle grade cells are supposed to store 202 Ah! This looks like the same part number as the dimensions are the same as these shady "120-138Ah" cells.

This isn't grade "B" cells this is grade "F we stole it from the reject bin" cells. Not a good move, there must be massive internal faults for a 202Ah cell to test out only at 138, I would not expect it to last 10+ years, these things are industrial waste.

According to this article from 2020, blade batteries were initially indeed 138Ah

The road to BYD's counterattack? Blade battery "first show", selling point of higher safety - DayDayNews

(This article was first published exclusively on the Tencent News client, please do not reprint without authorization.) On March 29, BYD's "blade battery", which has been discussed

daydaynews.cc

 

[BrickedKeyboard]

Ok so I have an idea. 4 blades next to each other and flat on a cement board to fit on a shelf, similar to the ones home Depot sells. Zip tie them to the board with metal zip ties. Then the next bank of 4 on its own cement board goes on top and so on. So 4 of these cement board + battery combos go on a shelf, then a 5th cement board and the BMS goes on top of that as well as the T class fuse, giving you a 16s.

Update: for a shelf the Husky's Steel I-Beam Shelving Unit claims 2500 lb capacity per shelf, it's 5 high. Should easily hold these batteries, possibly 2 per level.

Maybe screw a few lexan panels on the end and sides once you have the wiring done so visitors to the shed or garage won't cause a short when they drop something conductive.


If the shelving rack can take the load (about 200 lbs per battery) you could put 3 batteries one above the other and run your main bus cables between the 3 top boards that have the BMS and fuse.

This whole assembly goes in a shed or garage (something in a separate air space than a dwelling) and you stick it where the short end where all the batteries and cables are is accessible.

The cement board is both acting as a spacer and will act to soak up any thermal events if a battery goes bad or theres a short. These batteries should be safer but cement board is super cheap.

 

[eXodus]

Zip tie them to the board with metal zip ties.

don't use metal zip ties.
The cells expand and contract with every charging - they will rub through the case eventually and you got a nice sparkling event.

Get the data sheet and see what compression value is specified.

But I like the Cement Board Sandwich idea. Cement board - battery blades - cement board.

The cement board is both acting as a spacer and will act to soak up any thermal events if a battery goes bad or theres a short. These batteries should be safer but cement board is super cheap.

For stationary application - mass is always good. That not also soaks up thermal events - but makes the battery more thermal stable. It will heat up slower and doesn't cool down as quick if you get a few unexpected cold nights.

 

[BrickedKeyboard]

 

[BrickedKeyboard]

So ok, $1080 is getting even more reasonable. Not sure if this is the lowest available (I'm not ready to buy just yet) but this is good.

I looked at the specs for these batteries. On paper you can discharge them at 2C. This means 2 * 138 = 276 amps!

Why would you do this? It means with the appropriate BMS (like the 250 amp common port Daly one) you could drive a growatts 12,000 watt model on just one battery. (250A * 50v = 12.5 kilowatt)

For somewhere like San Diego, where you can get an EV TOU plan, the battery just gets you between 4pm and midnight, and between 6am and 8-10am. You then can charge for 10 cents a kWh at night, and obviously get solar in the day. (and in a few years if they take the plan away, you add more batteries)

Other than 16 batteries, you need the BMS ($216), fuse ($13), disconnect switch ($33), precharge resistor ($2), and 5 cement board ($50). $1394 for a 138 ah battery you can discharge at 250 amps. That's a bit more than you get with the server rack batteries though a lot of hassle to build it and those Daly BMS have a bad reputation for reliability. $197 a kWh.

EV manufacturers are getting their completed batteries for $132, so this isn't as inefficient as it sounds. Could use a cheaper Overkill BMS and less cement board and spend 182 a kWh.

 

[luisenriquereyes]

View attachment 79183

Each piece can be as low as $42 each with screws and bus bars. This is the latest price list I received today from Jack at Shenzhen Zhongtong Battery CO :

 

[JoeHam]

That seems like a great price, unless shipping is like a million dollars ?

Following along with your progress.

 

[BrickedKeyboard]

That seems like a great price, unless shipping is like a million dollars ?

Following along with your progress.

It's the same vendor I have a quote from above. So unless they are bait and switching the shipping should be the same.

Assuming it is then this is a $7.6 discount per battery cell or $121.6. then you can save money going with an overkill 16s 100amp BMS, about $153 instead of $216.

So $184 in savings. Let's say you skimp on the cement board and use just 3 pieces, saving $20. So $1190 for a 7.065 kWh battery or $168 a kWh.

Though you still need some 2 - 8 gauge wire to hook it all up, ring terminals, heat shrink, and a shelf and some clear plastic panels to protect from shorts.

More and mor those server rack batteries seem like such a good deal. None of this hassle and it's a lot harder to screw up with one since they come in a nice metal case with a circuit breaker. Most faults will just blow the breaker, if it catches fire the relatively low energy lithium iron fire probably won't escape the case, all those terminals are protected inside there.

Honestly maybe the right answer is we just order a server rack battery through Alibaba. If you can get one delivered for $1100 that's $214 a kWh.

 

[JakobT]

I don't know to me they seem too good to be true.
Also hard to find other sellers, makes me suspicious. I also contacted Jack about a delivery to Germany. If they are for real, I would actually consider building a battery again. That's finally a price point, where custom building starts making sense again (to me). But I agree, if you can get an "OK" ready made battery at just ~50% more than the same capacity in pure cells... it's hard to justify custom building (even if you enjoy the building process it like I do :D).

 

[danibzibur]

But seems like these blade cells are safer than standard prismatic cells:

I want to know what happens when that nail goes in Sideways, cause in real conditions with presumed 16s assembly and mounting in EV flooring, that is how they 're going to get stabbed.