What wire and connectors should I get?

I know this is probably discussed to death somewhere but it's almost impossible to find a thread on wires and connectors that gives me the info I need by searching those keywords as they show up in almost every thread.

So I was hoping you guys would be able to help me out on choosing what kind of wire and connectors to buy. I will be running a 20s lipo setup using the 4s1p5ah20c Turnigy hardcase batteries: http://www.hobbyking.com/hobbyking/store/__15521__Turnigy_5000mAh_4S1P_14_8v_20C_hardcase_pack.html My controller supposedly pulls around 30amps peak, although it is rated for 40. I am looking at buying cheap wire and small connectors that will be lightweight, but if I need to buy more expensive stuff for better performance I am willing to do that. I know anderson powerpoles and 10awg wire seem to be popular, but do I really need those? Can I just use the 4mm bullet-type connectors that are already on the batteries instead, or just directly solder the wires to each other instead of using connectors? I plan on bulk charging so I don't need to take apart the batteries unless one of them needs replacing.

I was looking at buying the 10awg turnigy wire from hobbyking and 30amp andersons from ebay. Will the 30 amp andersons fit the 10awg? And does this seem like something I should buy or can I get away with a lower quality wire?

Thanks so much in advance!

I've been pulling 56 amps constant through those 4mm hobbyking bullets and running very short length 10awg battery cable for a few weeks now on my DD bike. No problems. No connector heating either.

For wire i wouldn't bother shelling out for anything fancy. All my wire is from my local car parts store, lol. Pure copper ftw..

The wimpy 16ga. phase wires on my hub motor tho.. that's another story

Here's a little tutorial for soldering the 4mm bullets.
http://endless-sphere.com/forums/viewtopic.php?f=14&t=28694

I ended up buying some 10awg and 16awg wire along with the 4mm bullet connectors. Thanks guys!

What are you going to use the 16awg wire for?

That stuff is so small that it won't fit in the bullet connectors.
The minimum would be about 12ga.

I find Andersons hit and miss, easy to heat up so I use XT60 connectors. Much more reliable.

12Awg is good for 30amps but 10Awg would be better. I've been running 12Awg on my phase wires in the HS3540, they don't get warm but could do with upgrading.

I've run more than I should through 12 guage, and 45 amp andersons. 100v 40 amps at one time. No wires got that hot, but one flaky connected anderson can sure melt down fast if that happens.

I went and put 45 amp andersons on about 16 of 24 lipo packs, and now I kind of regret it. New packs I want an anderson on now get an adapter. A short wire with a bullet on one end, and the anderson on the other. For paralell packs, it's a bullet on one end and two bullets on the other end, or for the two wires that go to the controller, two bullets and a longer wire that terminates with an anderson at the controller.

When I converted every connector it made sense to me because I wanted to paralell or series connect batteries at will for multiple bikes using different voltages. Andersons seemed a good way to do that. But then I found them unplugging themselves, backing out of the housings. etc. All solvable problems, but a bit of a pita.

So what I want to do from now on is, make all the connections with bullets except that last one to the controller. That connector gets a big spark. For the spark, and anderson works better. The tip fries, but the main connection stays in better shape.

I just started using this, on my 10s or 12s rigs. pretty handy. In my case, only discharging 22 amps on those bikes. http://www.endless-sphere.com/forums/viewtopic.php?f=4&t=32096

It would be a lot of wire for a 20s 10 ah rig, but maybe worth it if making charging easy is the main goal.

Reading your post again, you might want to start out by making your packs look like this to start with. Cut both connectors off halfway down the wire, then solder or connect somehow just one wire with the attached bullet.

In my case, I find it nice to use the shown crimp sleeve. Crimp with a regular crimper, crimp into a V shape, then fold the V shut real tight. Then cover with two layers of heat shrink to insulate. I get the crimp sleeves at the home depot or whatever. They are intended for house wiring.

Now you can just make series connections with the bullets no problem if the wire is long enough. If you need more wire length, attach longer ones instead of re using the cut off connector. Then at the terminal ends of the pack, add a bullet to anderson wire long enough to reach the controller.

If you choose 10guage, you will have to use 45 amp anderson contacts, and they will be harder to stuff into the 15-30-45 housings. 12 guage and 45 amp contacts is easier to work with for sure.

Lastly, you can paralell the balance wires if you wish to, by buying 4s jst extension wires. Sort them for the good ones, some will be flaky so buy several bags. Then splice them into y connectors to parallel the balace leads.

neptronix said:

What are you going to use the 16awg wire for?

That stuff is so small that it won't fit in the bullet connectors.
The minimum would be about 12ga.

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Just bought some for using with regen brake lines and whatever else I might ever need some thin cable for. The battery and phase wires that lead to the controller look to be about 16ga. Should I maybe replace these with 12? It would destroy the waterproofing so if it's not going to make a big difference then I'd rather leave it the way it is.

dogman said:

Reading your post again, you might want to start out by making your packs look like this to start with. Cut both connectors off halfway down the wire, then solder or connect somehow just one wire with the attached bullet.

In my case, I find it nice to use the shown crimp sleeve. Crimp with a regular crimper, crimp into a V shape, then fold the V shut real tight. Then cover with two layers of heat shrink to insulate. I get the crimp sleeves at the home depot or whatever. They are intended for house wiring.

Now you can just make series connections with the bullets no problem if the wire is long enough. If you need more wire length, attach longer ones instead of re using the cut off connector. Then at the terminal ends of the pack, add a bullet to anderson wire long enough to reach the controller.

If you choose 10guage, you will have to use 45 amp anderson contacts, and they will be harder to stuff into the 15-30-45 housings. 12 guage and 45 amp contacts is easier to work with for sure.

Lastly, you can paralell the balance wires if you wish to, by buying 4s jst extension wires. Sort them for the good ones, some will be flaky so buy several bags. Then splice them into y connectors to parallel the balace leads.

Click to expand...

Wow that's pretty much what I was looking for dogman, thanks! I was thinking about just wrapping the wires together from the batteries to parallel them but crimping sounds like a better idea (time for another trip to home depot now lol). I would order some of those balance harnesses but they'd be the last part to come in the mail and I'd just get too impatient and probably just strip one of the balance leads half way down and solder the other battery's balance leads to the first. Any reason why I shouldn't do this?

Thanks for the help so far everyone, it's much appreciated

On my 20s pack running a 65 amp 18 fet Lyen controller, 10 gauge wires from the pack to the controller is fine.
As are the 4mm bullet connectors.

I see peaks of 120 amps and see constants of 72 or so on the CA when up at speed. The ires get a bit warm but not much..and that is more due I think to the proximity to the controller

Regarding the picture above of the batteries, connectors and splice. That looks like quite a big join and very solid .
If you are tight on space when you come to pack the wires in the battery box...that could be an issue. I also have big joints like that and they are a bloody pain.

There is posts that state that for best balance of the batteries, all leads in the parallel harness to each battery should be the same length. In theory that is correct, but again if you are tight on space, you will then find that having all the lead the same length will result in a mass of wires that you can't compact down. I scrapped my first wiring harness and re made with each battery in place, and each wire only just as long as it needs to be, so they all fold down flat against the tops of the pack, unlike the previous harness, when they were all the same length.

So for you needs 10 gauge a 4mm bullets will be fine...just get the bullets and heat shrink them to insulate them...the plastic housing type just take up too much space

Personally, I'm in the minority that doesn't paralell the balance leads permanently. For one, I want the individual plugs to remain so I can figure out which pack to toss and which to keep when you do get a bad cell. So when I do want to balance charge them on the RC charger, I will put the paralell leads on the balance wires for that charge.

The rest of the time, I'm just doing the fast charge cycle, and not balancing. So I don't bother with balace leads. Mostly, I just want the balance leads short and out of the way.

I suppose it depends on how you use the packs. If you permanently install the packs into a bike, then permanently paralelled balance leads make a lot more sense. And some extra wire leading to a port where you can check the cells or attach a cellog while you ride. I move the batteries from bike to bike constantly, so I always have easy acess to the individual jst plugs when I want to check the cells.

Definitely, it's an eye opener how much space the wire and connectors can take on a pack larger than 4 lipo bricks. Here's a nice tangle on one of my bikes. box for 72v 15 ah, 12 batteries.

cough.. solder please... $10 butane pen torch and $4 can of butane and some solder does wonders.. I have to try mechanically crimping but I know the sleeves will accept (4) 14g and (3) 12g wire with (1) 12 or 10g wire.

I prefer silicone cause it doesnt act retarded with extended exposure to heat while soldering....pvc automotive is ok and easier to solder but the insulation gets soft and tacky super quick...

Crimps are good when done right, horrible when done wrong. Practice either way first on other wire, whether you crimp or solder. On the pack is not the place to learn either.

dogman said:

Crimps are good when done right, horrible when done wrong. Practice either way first on other wire, whether you crimp or solder. On the pack is not the place to learn either.

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Wise words practice makes perfect.. those pack leads get short after you fudge up a few times

Yeah, another tip so obvious we shouldn't have to say it, but......

Don't strip the wire on both wires at the same time. Work on the red or black first, get it nice and insulated again with heat shrink, then strip the other wire.

Lots of good tips guys, very much appreciated. I'll be placing the batteries in a slim backpack so I need to take up as little space as possible. Judging from member Karl's pictures of his lipo backpack, mine should just fit but I need to watch the amount of space the wiring takes up. I'll decide on what to do once I get the batteries and bag. For now I get to play the waiting game as all my parts start to come in. My next job to do is set up my 2 meanwell clones :|

Im using XT60 for everything but not the phase wires.
Phase are usually done with bullet or XT150.

Good quality short wires(1,5meter) @ 12awg ll take at least twice as much current, if not more before giving you trouble.

Interesting to read the comment about the balance leads and permanently connecting them
I never permanently fixed mine either, they are all connected up with a parallel harness with plugs so can be individually removed if necessary.
That said, in the 7 months I have had this bike, I have only taken them off twice and that was in the first month to check each pack after a few cycles. It was such a pain doing it and once they are balanced and setup they seem to stay that way. But I still would not permanently join them up

I don't parallel balance leads either. I guess the thought of a weak cell trying to equalize through thin balance wire gives me pause. What if one cell is a puffer and/or contaminated? It seems to make sense that it could possibly become unstable while electrically connected to other good cells? If I got a bad one I wanna know about it and get it out of the pack assembly. But I also know a lot of smart folks do parallel balance leads so it probably works itself out in some manner?

Ditto on Dogman's Anderson advice - If I were doing this again 'would keep the bullets on my bricks and just make adpaters for any other configurations.

btw - I'm in the 30-35A range and reliable running 12ga wire with 30-45A Andersons, less than 1ft wire runs.

Ykick said:

I don't parallel balance leads either. I guess the thought of a weak cell trying to equalize through thin balance wire gives me pause.

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Wait, so you're not supposed to parallel the balance leads at all? I thought they should be balancing between the balance wires.

It seems the majority parallel the balance leads. The advantage of this is that if a cell becomes weak, it will draw current from it's paralleled mate until the voltage equalizes. The capacity of these 2 cells will now be lower than the healthy cells, but significantly higher than the initial capacity of the one weak cell.This will gain some extra headroom when discharging, to avoid hitting the critical 2.7v. Some choose not to parallel. The main reason being, In paralleled balanced lead packs, if the weak cell dips below the critical 2.7v point, it's paralleled mate will get dragged down simultaneously, possibly destroying 2 packs, rather than just one (if not paralleled). This applies for charging as well. Pick your poison

psycholist said:

It seems the majority parallel the balance leads. The advantage of this is that if a cell becomes weak, it will draw current from it's paralleled mate until the voltage equalizes. The capacity of these 2 cells will now be lower than the healthy cells, but significantly higher than the initial capacity of the one weak cell.This will gain some extra headroom when discharging, to avoid hitting the critical 2.7v. Some choose not to parallel. The main reason being, In paralleled balanced lead packs, if the weak cell dips below the critical 2.7v point, it's paralleled mate will get dragged down simultaneously, possibly destroying 2 packs, rather than just one (if not paralleled). This applies for charging as well. Pick your poison

Click to expand...

For those that worry about any of this there is an easier solution now-->

http://endless-sphere.com/forums/viewtopic.php?f=31&t=32460

KiM