[brian_]

"HVH" means High-Voltage Hairpin. The "hairpin" part is about how the stator is wired and you can ignore that to some extent, but the "high voltage" part is critical. There's no point in using one of these unless you're running it close to the intended voltage... and for the lower-voltage HVH units that is well over 300 volts.

Controller wise there are a few of these curtis ac controllers second hand for relatively little money are they man enough for the job think these are for forklifts so probs low mph voltage?

https://www.ebay.co.uk/itm/Curtis-M...414267?hash=item2f0d687c3b:g:FmUAAOSwehZZ7IL1

The operating voltage is clearly given in the specs for these controllers. While eBay may be suitable source of cheap controllers, I wouldn't trust any technical information in the listings. Curtis controllers come from Curtis Instruments, which provides lots of authoritative information about them. Yes, they are mostly used for forklift trucks and other industrial equipment, plus golf cars and other small non-roadgoing vehicles. DIY EVs using relatively low (by current standards) voltage appear to be an accidental sideline for them.

These are my other battery options then opposed to NiHM

https://www.ebay.co.uk/itm/Toyota-P...377406?hash=item3d49c0cdbe:g:-qUAAOSwYyVZewW3

Lithum ion prius batteries approx £700 savaged - maybe 2 or 3 of these £2100

https://www.ebay.co.uk/itm/Tesla-Mo...325925?hash=item1c96842125:g:-4EAAOSwTm9Z-Esw

Tesla Module salvage £800 maybe 2 or 3 of these £2400

Prius batteries are configured for a reasonable voltage, but 2 or 3 of the 16 modules in series will provide a voltage level more appropriate for a golf car than anything using an HVH motor.

Could an DC/AC inverter / charger system be used from one of the salvaged vehicles or are they to integrated within the system of the vehicles to operate as a standalone unit?

While in theory an inverter from any EV with a permanent magnet AC synchronous motor at a compatible voltage might work, they are highly integrated with the vehicle. There's no way to use them unless you either emulate the CAN network messages that they are expecting, or replace the logic portion (a serious electronics and software project). I'm no expert on this, but I haven't noticed anyone in this forum using an inverter from a production EV except with the motor that it came attached to... and even then it's a challenge.

 

[brian_]

... one of these AC Control/Driver boards from PandSpowerelectronics in Canada...

Looks like it has potential.

By the way, P&S Power Electronics appears to be in Arizona, not Canada (judging from information on the company and store websites). I think it is the business of MPaulHolmes of this forum.

 

[brian_]

Almost every EV on the road uses battery packs comprised of 18650 cells.

That's not true at all! Tesla uses cylindrical cells (18650, but now switching to a larger format), but as piotrsko mentioned, other major players currently use pouch cells; most manufacturers (nearly everyone other than Tesla) use pouch cells and most have never used cylindrical lithium cells.

For example, modern GM electric and hybrid vehicles (Volt, Spark EV, Bolt) use pouch cellls - the Volt packs are popular among builders in this forum, such as piotrsko. The other popular source of modern battery packs for DIY projects is the Nissan Leaf - again, these are pouch cells.

Speaking of GM...
Remy, builder of the HVH motors used in GM hybrids and EVs and subject of this topic, was a division of General Motors for 75 years and is now part of BorgWarner; these motors are now branded "BorgWarner", not "Remy".

They have 4 times the energy density of conventional cells and they’re capable of deep cycling.

18650 is just a physical case format: 18 mm diameter, 65.0 mm long. There are many different cells offered in this format, so to assume a specific level of performance is not valid. There are several lithium chemistries, but typically they are suitable for deep cycling... in 18650 cylindrical cases or any other physical format.

Also, the performance of any cell is highly dependent on electrical and thermal management: you can't just take the same cells as used in a Tesla Model S, stick them in a closed box without cooling, wire them to a controller without monitoring, and expect Tesla Model S performance.

 

[brian_]

I stand corrected, 18650 cells are used in Tesla’s but they are moving to a 17670 format.

Okay, but the point was that any kind of cylindrical cell (18650, "17670", 2170, or any other size) is not used by most manufacturers. They use entirely differently packaged "pouch" cells.

The cell actually used in the Model 3 is the 2170 format cylindrical - 21 mm x 70 mm - made by Panasonic at the "Gigafactory".

 

[brian_]

I haven’t seen a DIY pouch battery made from scratch and as this is a DIY EV forum, the suggestion was to make one from 18650s which is far more common.

Sure, that makes sense if completely from-scratch pack construction is required. On the other hand, welding fine leads to every one of those cylindrical cells is a real pain for DIY manual construction... which is one reason that people were using prismatic cells (with a small number of connections, using screw terminals) and now avoid building packs from individual cells at all, instead assembling OEM modules (consisting internally of of pouch cells) to suit their needs. Even when people use 18650 cells, most of those cells going into recent projects are within complete Tesla modules, not as individual cells; some people do modify the Tesla modules (to change them from 6sNp to 12s(N/2)p), but even then they don't touch the individual cell connections.

Since sdb's intent is to convert a camper or van, it should not be necessary to custom-build a pack to suit some oddly shaped cavity; reconfiguring the modules of a production EV pack (whether those modules contain pouch cells or cylindrical cells) seems like the most practical approach.