Best high current connector

Hi everyone,

I'm building my own 8wk ebike and have got to the point where I need to put connectors on the ends of the battery pack. Originally I was thinking of using anderson connectors as they looked very suitable and easy to use. However given that I need them to carry 150a and fit a 3-4awg wire, the cost comes to around £80 just on connectors (ouch!) Does anyone know of any other styles of connectors that can easily be connected together and have a wire crimped onto them? I thought about adapting some XT90s but the push fit is too tight and the enclosure is now a tight fit with the cells. I'm prepared that I might just have to go for it, but if there's another option I'd rather have a look at it as well.

Thanks

...8 kw ebike
...150A
...3-4 AWG wires

Up the planned voltage. You will save money and weight in wiring alone.

Andersons are expansive but hard to beat for safety and reliability. Any big crimped connector in a safe housing will be expansive.

As Madrhino said, any good connectors will be expensive. However:

There are cheaper imitation Andersons. I ordered a set from Aliexpress, the quality seems adequate, but I had them on an interior, stationary, very rare disconnect use case (been disconnected about 8 times now, minimal pitting on contacts, still a solid tight fit.) So not really the same as an eMotorcycle. I am using genuine for that.

Other alternative might be large ring terminals, if you aren't intending to disconnect often. (Charger on bike, etc.)

MadRhino said:

...8 kw ebike
...150A
...3-4 AWG wires

Up the planned voltage. You will save money and weight in wiring alone.

Andersons are expansive but hard to beat for safety and reliability. Any big crimped connector in a safe housing will be expansive.

Click to expand...

I wish I could, but the batteries I've chosen are high capacity and I simply can't fit any more in the frame. If I were to do this again I'd deffo go for higher voltage but it's all built now. I think I'll just have to bite the bullet as I'll probably regret skimping later. Any more suggestions welcome!

cg_ebiker said:

MadRhino said:

...8 kw ebike
...150A
...3-4 AWG wires

Up the planned voltage. You will save money and weight in wiring alone.

Andersons are expansive but hard to beat for safety and reliability. Any big crimped connector in a safe housing will be expansive.

Click to expand...

I wish I could, but the batteries I've chosen are high capacity and I simply can't fit any more in the frame. If I were to do this again I'd deffo go for higher voltage but it's all built now. I think I'll just have to bite the bullet as I'll probably regret skimping later. Any more suggestions welcome!

Click to expand...

For 150A there is a turnkey solution. A tenner for a pair.
The qs8/qs8-s/ec8/ec8-s
https://endless-sphere.com/forums/viewtopic.php?t=2767#p1317655

How often do you plan to remove the battery? I go years without touching mine, so I generally hard wire everything, and it saves time, expense and space.

XT90's are good but there are some "HV" bullet connectors from Hobbyking that look to do 150A.

Supra X solderless are good coin but can do 270A and 250A? contin.

To expensive for me, I build with those old thing called " bolt on copper lugs". They make them, that take like what... (afewthousand)A?

I just decided to use good lugs. Those XY90 antispark suck.. I have blew or burned all of mine .. THEY ARE 4oHMS! lol. My bike eats 4moh antisparks. You really need 100ohm - 1000 ohm for the precharge circuitry. I aint wasting money on a QS8-s rthat only lasts for like.. 4-6 months of connecting.

ZAP right through an AS... a few of the controllers I have here. Big big 200v caps and things. Low voltage is less of a prob. HV? >100v? ZAP.

I am building with 6Ga... and that is all ya need on an ebike power level, Id say. 6Ga can take ~700A for 10 sec.

As extreme opposite to John, I unplug mine many times a day, and my big Andersons are lasting years. Even after making them last with filing, bending and silver tinning, I only need to crimp a new one and insert into the old housing. Their only downside is size. If size is really important then go for 10mm gold bullets, but they are very far from the Anderson’s safety. A 10 yr old kid can handle big Andersons without any risk for himself or material.

Hopefully I won't have to disconnect very often at all, but as I said it's a tight space so the way the andersons clip together is very appealing. I also need something that can be crimped to and not sure if the bullet connectors offer that?

Anderson for sure

if you don't want to buy the proper crimper, ask around for shops will let you come by and use theirs.

Or genuinedealz.com is excellent for custom wiring, charge $1 per crimp on top of materials, top notch quality

Ok, I think anderson it is! I've already bought a hydraulic crimp for some lugs so I can use that. Thanks for the help!

Do not assume, most cheap hydraulic crimpers (under $500) are metric dies, not all sizes correspond well to the "nearest" AWG.

PowerWerx sells a very cheap knockoff of the proper Anderson crimpers, I think under $60, good enough for amateur occasional use.

That is good to know, I use XT90's and they seem to break at the solder joint or just behind it once a year. I undo my connectors 2 or 3 times a day.

You use Anderson Powerpole with the big plastic one piece 2 connector, SB50 SB175/120
They even bolt on a handle - https://powerwerx.com/anderson-power-sb50-hdl-red-handle

Or the normal PP45/75 ?

MadRhino said:

As extreme opposite to John, I unplug mine many times a day, and my big Andersons are lasting years. Even after making them last with filing, bending and silver tinning, I only need to crimp a new one and insert into the old housing. Their only downside is size. If size is really important then go for 10mm gold bullets, but they are very far from the Anderson’s safety. A 10 yr old kid can handle big Andersons without any risk for himself or material.

Click to expand...

I use the single connector housing. They are available all colors and can be assembled together on both axis. I use matching colors. Red-black for battery, blue-green-yellow for phases.

I find XT90 a dangerous design. I prefer single gold bullets to assemble lipo bricks together.

PP45 Andersons are sh*t. I would use another connector design if I wanted that small. They start being reliable from PP75.

MadRhino said:

PP45 Andersons are sh*t. I would use another connector design if I wanted that small. They start being reliable from PP75.

Click to expand...

Bigger and beefier housings on the PP75 vs 45?

Yep, and lots of PP45 are fake Chinese. PP75 are rated 120A but can take much more. Most of all it is from that size (49.9 mm long housing) and up that Andersons are making a robust, reliable connection.

I like XT150's. Easy to disconnect and pretty easy to solder if you have a decent iron.

These and the anderson look terrible from a water/dustproofing standpoint. Just huge ugly blocky plastics. Not for ebikes.

Tommm said:

These and the anderson look terrible from a water/dustproofing standpoint. Just huge ugly blocky plastics. Not for ebikes.

Click to expand...

It's all in an enclosed metal frame (enduro frame) so I'm not worried about water and dust

Tommm said:

These and the anderson look terrible from a water/dustproofing standpoint. Just huge ugly blocky plastics. Not for ebikes.

Click to expand...

And so...
Which of them sexy shaped, smooth finish, water and dust proof connectors are you using Tommm ?

skidmark said:

I like XT150's. Easy to disconnect and pretty easy to solder if you have a decent iron.

Click to expand...

You never see a solder-only high current connector in industrial machinery. Crimping is not only much faster and easier to do, it’s also much more reliable.

I like the form factor of XT90s etc., but I would only install them on my own equipment if they could be crimped.

Balmorhea said:

You never see a solder-only high current connector in industrial machinery. Crimping is not only much faster and easier to do, it’s also much more reliable.

I like the form factor of XT90s etc., but I would only install them on my own equipment if they could be crimped.

Click to expand...

I totally agree. That is why I suggested SupraX-RCProPlus Solderless. Nothing beats them and I have had (helicopters desolder in flight? AS-90 not an AS no mo? ZAP ).


"Specifications:
Peak Current: 310A
Continue Current: 260A
Applicable Wire: 6AWG only
Finish Type: 24K Gold Plated 5u"

https://www.amainhobbies.com/rcprop...WmBiZ2p2fheYX8oTBZeSX0coG0UCdCxoCDY4QAvD_BwE
If cost was not an issue I would use those exclusively for convenience and bling.... but lugs are cheap and reliable.. Bolted connections.. but not convenient... So I use lugs and hardwire everything. 150A and > 58v you should hardwire everything. Power there.

i mean, have we seen the OP 's battery yet? Not many of us have a battery that can really take advantage of "need them to carry 150a and fit a 3-4awg wire".... Who pulls 150A Contin?

I am currently building a few batts with, like I said, 31mm^2 busses ( cell to cell interconnections) (2Ga) and 13mm^2 (6Ga) wire leading from the pack. Many people overspec the wire but underspec the buss. It will get lugs, a precharge system, and quite a few temp stickers/sensors on the important parts. There will not be a hotspot on the buss for sure.

I got into this fight with the RC guys.. who think they need a two lb Anderson to handle the 200A current. nah. We fly helis, they are light, ....Andersons are for Forklifts and everyday industry.

Multipole Andersons are low voltage. Not for the 72-132v we like. You need a Singlepole Violet or White. I have only ever seen the White ( pretty sure.. ) in the scrapyard. I have those for scrap price + labor.. but they all Red or Blue or Grey... Lying around the scrapyard.

They are rated for very few Hot load connections. Like 250 Hot... , and 100,000 No load connections. They are not to be disconnected under load.

Correct, but a professional crimping tool is $200+ for that industrial/commercial setting. Way different connection quality then some low quality tool. Where as a soldering iron can be had for $5, solder for $5 and a baggy of XT90's for $10 or whatever the price is.

Balmorhea said:

You never see a solder-only high current connector in industrial machinery. Crimping is not only much faster and easier to do, it’s also much more reliable.

I like the form factor of XT90s etc., but I would only install them on my own equipment if they could be crimped.

Click to expand...

You never see a solder-only high current connector in industrial machinery. Crimping is not only much faster and easier to do, it’s also much more reliable

Click to expand...

Each has their strengths and drawbacks. If you live near salty-air environments, solder and marine heat-shrink can be useful in preventing severe oxidation.

That being said, crimps are less likely to fail from a temporary heat-spike. A soldered connection can partially de-solder from heat, and the remaining connection becomes a weak link that will fail soon.

Of course, heat increases line resistance. So any connection that is getting too hot to touch is a bad design, and is likely too small, whether it is soldered or crimped.