Ampster
Renewable Energy Hobbyist
There are several in the EV conversion space. The two I fam mentionon earlieer and am familiar with are Orion and Emus. Upthread someone else mentioned REC can go that high.
High Voltage DIY LiFePO4
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OffGridForGood
Catch, make or grow everything you can.
This is interesting, since high series BMS's allows a DIY high voltage LiFePO4 as a possibility.
This means a way to avoid other Li-ion chemistries, or custom built (expensive) LiFePO4.
I can imagine a 112-S, 304Ah cell LiFePO4 pack - even if the BMS is $800, you would only need one to build a 109kWh battery, my current 53kWh ESS in 48 volt is using five BMS's, and to expand to over 100Ahr will take four more, costing a lot more than $800 for similar capacity.
Now I feel that when I get to 7 DIY 16S batteries, I may be tempted to re-arrange them into a single 112S HVDC pack...maybe it is a good thing I don't have that many cells...yet.
Although...I can think of someone (WP) who likely Does have 112 cells laying around...
Check out the website for REC BMS, lots of very interesting features with these BMS's and a lot more refined controls. very interesting.
This means a way to avoid other Li-ion chemistries, or custom built (expensive) LiFePO4.
I can imagine a 112-S, 304Ah cell LiFePO4 pack - even if the BMS is $800, you would only need one to build a 109kWh battery, my current 53kWh ESS in 48 volt is using five BMS's, and to expand to over 100Ahr will take four more, costing a lot more than $800 for similar capacity.
Now I feel that when I get to 7 DIY 16S batteries, I may be tempted to re-arrange them into a single 112S HVDC pack...maybe it is a good thing I don't have that many cells...yet.
Although...I can think of someone (WP) who likely Does have 112 cells laying around...
Check out the website for REC BMS, lots of very interesting features with these BMS's and a lot more refined controls. very interesting.
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yabert
Solar Enthusiast
Why? I don't understand why you don't group 7 cells in parallel to create a single 2128Ah cells and then put 16 cells in serie.
And if you want more output power (amps) out of your BMS, simply use a relay BMS. Here an example with 15 kW capacity (300A x 51V): https://batteryhookup.com/products/7s-21s-24v-75v-300a-lithium-ion-bms
You can be this guy. Simply buy 112 cells 18650 for less than 100$ ?
Hedges
I See Electromagnetic Fields!
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REC is about $800 for 16s. If you need 112s, I expect something like $5600 maybe $4400 if it means only one $200 contactor.
But I haven't priced it out, tell us what you find!
OffGridForGood
Catch, make or grow everything you can.
You are correct, the REC is based on 16S modules each with it's own BMS controlled by a Master.
To achieve 112-S, this system would require 7 modules of 16-S plus the master controller. The control and details available in the REC are very impressive, they have some short video clips on their website that provide a quick overview. Costs would be in the $4500-5000 range.
The Orion and EMUS. Still digging into these units.
Orion has large cell count BMS in multiples of 12, from 24S to 168S - no 112S, would have to choose either 108S or 120S.
MSRP for these is about $1300USD. More research underway, there is a lot to review.
To achieve 112-S, this system would require 7 modules of 16-S plus the master controller. The control and details available in the REC are very impressive, they have some short video clips on their website that provide a quick overview. Costs would be in the $4500-5000 range.
The Orion and EMUS. Still digging into these units.
Orion has large cell count BMS in multiples of 12, from 24S to 168S - no 112S, would have to choose either 108S or 120S.
MSRP for these is about $1300USD. More research underway, there is a lot to review.
Same here: https://m.aliexpress.us/item/3256804396944825.html?spm=a2g0n.detail.1000014.6.39e4Kc3MKc3MM1&gps-id=platformRecommendH5&scm=1007.40000.326746.0&scm_id=1007.40000.326746.0&scm-url=1007.40000.326746.0&pvid=0ea844ad-1608-4612-968a-68fbd79b8dc9&_t=gps-id
latformRecommendH5,scm-url:1007.40000.326746.0,pvid:0ea844ad-1608-4612-968a-68fbd79b8dc9,tpp_buckets:668#2846#8112#595&pdp_npi=3@dis!USD!435.0!435.0!!!!!@2101c67a16818756174392546e1904!12000029714860867!rec!US!135507165122S for $985
or 120S for $904
or 103S for $870
or 100S for $835
Ampster
Renewable Energy Hobbyist
The Orion is centralized and they allow you to wire them for fewer cells. For example the 120S unit can handle 109 to 120S.
The Emus is decentralized with a central control box and individual sending units on each cell which are networked. I have had a good experience with both.
OffGridForGood
Catch, make or grow everything you can.
I didn't realize Heltec had these. interesting.Same here: https://m.aliexpress.us/item/3256804396944825.html?spm=a2g0n.detail.1000014.6.39e4Kc3MKc3MM1&gps-id=platformRecommendH5&scm=1007.40000.326746.0&scm_id=1007.40000.326746.0&scm-url=1007.40000.326746.0&pvid=0ea844ad-1608-4612-968a-68fbd79b8dc9&_t=gps-id
122S for $985
or 120S for $904
or 103S for $870
or 100S for $835
OffGridForGood
Catch, make or grow everything you can.
Yeah, in 18650's or 32700 (e-bike stuff) I DO have enough cells, but not really what I was after, LOL, then again I would only need 92 of those cells to get to 360v LOL!!
I would be most interested in getting a used EV battery from a local Wrecker for CHEAP and play with that!
however, also interested in the idea of DIY-HVDC LiFePO4 Battery or at least figuring out if such a thing is possible, and what it would cost in current market. Looking like 112 cells at about $110 each = $12,320 plus shipping likely another $1400 so that is $13,720. Add a $1200 BMS cables, fuses, and build a bullet-proof box lined with FR4 and restrain everything. About $16,000 for a DIY LiFePO4 100kWh 360vDC battery pack.
I already have three DIY 16-S racks and four more planned. 7 racks x 16 cells each happens to be...112 (and thus my obsession with 112-S !)
Wouldn't it be cool to be able to reuse my 16s racks to build a HVDC future rack, or my other wild dream idea, an EV conversion from a 1987 Mazda B2000 mini pickup truck. What did you call that one you have? oh yeah the "battery on wheels in the driveway"
yabert
Solar Enthusiast
Haha! Yeap, super useful battery. Can power the house in the morning and go shopping lumber to the Homedepot in the afternoon ?
No, there are LFP cells, so you need 112S. Generally, 360V EV battery pack are 96S when there are not LFP cells.
For 16k$ you can clearly have a complete 60 kWh or 75 kWh crash Tesla 3 to build your dream. What do you think about a 300-400 hp electric B2000 ??
A conversion like I did is only rely on mechanical integration skills. My Vanabolt still think it is a Bolt because I don't have to reprogram anything of build a battery because I reuse most of the components. So the Bolt is working as a Bolt despite it is inside a Vanagon body. You can do the same for a B2000 conversion. If your budget is lower, crash Bolt cost around 5-6k$ those days.
Back on subject, what is the advantage of an high voltage battery for you instead of a regular/safe/easy to build 48V?
OffGridForGood
Catch, make or grow everything you can.
My thoughts on this:
I am planning an ICE to EV conversion, and could pick any suitable battery type and voltage I like. I could source a wrecked EV and reuse it's battery/motor/controller and I likely will go this route, if I can source the required wreck. Likely the wreck will not be LiFePO4 chemistry. To have LiFePO4, I could build 7 x 16S packs and series connect them to get 360vDC for the EV, however there are issues with series connecting the 48v packs, and having a suitable BMS for each pack that will support the series connections, and a master to control them all.
A simpler method available is a single high cell count BMS that can control 112 cells, and maintain their balance without series connecting smaller packs, and make use of safe LiFePO4 cells.
My ESS home solar system is currently using 48v (16-S) packs. It could be charged with an Inverter that supports high voltage DC MPP inputs and supply that input from the EV instead of a high voltage PV string.
Available currently are also HVDC inverters, that would operate with an energy storage battery at 360v.
If the EV and ESS are both 360vDC, this would very much simplify rapid charging the EV, or the ESS, without expensive commerical DC chargers required, only control over the current flow. Additional equipment/machinery/systems that all use the same chemistry and voltage would share similar advantages and allow further back-ups to the ESS/EV/other.
If the Mazda EV conversion is built with a battery, fixed between the frame rails (for example) and has say a 160 mile range, but an additional identical voltage and chemistry battery pack is available, that can fit into the truck box, be secured and plugged in when longer range is needed, increasing the truck range to 320 miles wouldn't this 'modular' battery system be worth investigation? Effectively you don't have to choose a long range or standard EV, you can have both, and for daily commuting, not drag around the heavier long range battery, only install that when needed. Leave the spare extra-range pack on a rack in the shop where it is connected to the ESS as a dump-load for the stationary system. In winter, when no dump load is required, the spare pack can be charged overnight on our new Ultra-low-rate 2.4cents/kWh 11:00pm to 7:00am rate and be the emergency power when the utility is down during winter storms.
Say this same mobile 360vDC battery can fit into an off road vechical, and or a farm tractor, and or a house boat, or just sit on the rack in my work shop to add winter-time capacity to my existing ESS system, or power my neighbour's house in an emergency. (yes I have a fork lift and other equipment capable of lifting/manipulating such a heavy battery) could this not be a super versatile modular power system, using low risk LiFePO4 cells, and currently available parts?
Maybe I am just dreaming, but it seems worth the time to discuss and think about a modular system. I'd like to call it the "ESC-360" {Energy Storage Cell - 360 (360-voltage, and the idea is can be "turned 360-degrees to operate anything") and build about ten things it can fit into and just plug in and go.
OffGridForGood
Catch, make or grow everything you can.
I wrote to Emus and there engineering tech replied very quickly with some points and questions. I am interested to see what they can suggest and how their system would compare with the Orion, both the technical capabilities, and cost. This is an interesting direction I never thought of when building the 16S packs.
Ampster
Renewable Energy Hobbyist
I think both EMUS and Orion have specific products designed for the 16S segment. Because the larger systems typically are used in EVs the 16S versions do not have all the various interfaces usually found in EV conversions. Some of those are J1772 EVSE interfaces, Limp mode for inverters or motor controllers and CAN communications with chargers and displays.
yabert
Solar Enthusiast
I have this kind of versatile battery for the wood chipper, the snow blower, the cargo bike, the chainsaw (backpack), the mower, but it's at a reasonable 52V (14S NMC).
It's seem that your toys are way more energy and power hungry than mines ?
To me, voltage around 48V is good to power anything up to the range of 15-20hp (peak, not continuous).
Well, despite if you skip the official CCS combo protocol for charging in DC you will still need a kind of powerful DC-DC converter.
I don't see anything ''much simplify''.
3 points:
1-I have 150 miles/250km of range with my atrocity aerodynamic/large front area of Vanagon with his ''small'' 60 kWh battery, so your B2000 will clearly have 320-450 km of range with a 60-80 kWh battery pack.
2-Don't underestimate fast charge stations and your need to stop each X hours for lunch, for break, to pass water. There is more and more charge station everywhere and it's kind of tough to be at more than 100km of a charge station those days. Take a look on Plugshare.com.
3-It's a kind of dream and it work perfectly for scooter and their 35 lbs batteries, but it's clearly not useful and make no sense for a car when you realize how many charge station there is everywhere.
yabert
Solar Enthusiast
An EV is way more than battery/motor/controller. Charge port, heater, charger, DC-DC, connectors, cooling pump/devices, brake booster, accelerator, power steering, etc.
Also, today car are computer on wheels so you will need many modules and their programations to been able to have a decent EV.
You can choose to buy ($$$$) all those other parts need for a conversion or, more simply, reuse everything from the wrecked car.
OffGridForGood
Catch, make or grow everything you can.
Very true, I am on an ICE-EV conversion site, mostly reading and learning.
I suspect you live in a place with a lot more people, and places to charge than I do...LOL besides, I'd rather play with my modular battery idea than pay for a charging station! LOL. You are correct that more and more charging stations are coming - it is only a matter of time.
Our favourite fishing and camping spot, we need 450km range round trip, no-where to gas up or charge up on that trip.
I suspect you live in a place with a lot more people, and places to charge than I do...LOL besides, I'd rather play with my modular battery idea than pay for a charging station! LOL. You are correct that more and more charging stations are coming - it is only a matter of time.
Our favourite fishing and camping spot, we need 450km range round trip, no-where to gas up or charge up on that trip.
Ampster
Renewable Energy Hobbyist
Good point. At my age I have to pass water every two hours. If I do that at a Supercharger, by the time I find the urinal, get my zipper open and some flow, then take the time to empty my bladder, and then make sure my pants are zipped, my Tesla has another 150 miles of range.
Ampster
Renewable Energy Hobbyist
I agree. That is why my one and only EV conversion was a 1973 VW which did not have any computer interfaces so all I needed was a battery, motor and controller. Also I needed an adaptor plate and a shaft coupler so the motor could bolt onto the transaxle without needing motor mounts. It was a perfect EV for local driving in my small beach town. It could also legally go on the state highway that went through the middle of that town compared to the expensive golf carts that several people drove around town and were limited to 35 MPH at the most.
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OffGridForGood
Catch, make or grow everything you can.
Not at att. Attracting members such as yourself to take this thread to new levels was exactly my intent when I started it
.Who knows, maybe we’ll eventually get a dedicated subforum on the subject of DIY HV batteries (could take a while though!).
For now, The Danger Zone seems to be the most appropriate subforum.