Charging arrangement

[shorza]

Newb, you are a great help, thank you. I think you need to change username.

The charger is already bought, I couldn't justify the extra $50, although will probably later on.
I'm expecting short bursts of 50amps, but you know how it is, if you have the power, you will use it.
I already have a cycle analyst, so that will be my lvc and amp limiter.

I didn't want to get started to find that I was WAY off the mark. I am fairly comfortable soldering the 6 xt60 connectors on the batteries. I'm slightly worried about storing and charging lipos in my apartment. I'll have to be super careful.

 

[newb]

no worries mate, glad i could help. i've been reading ES most every day for a yr, electrified 5 bikes and im still just a NEWB.

just be sure the xt60 parallel & series wires are at least 12ga then, im not familiar w/ them so i can't say.

also, something not mentioned before is that running that kind of power to your motor (which is?) may be problemattic. especially if its geared and especially if you live in a hilly area as you will be pulling high amps frequently which can cause overheating issues. you may want to limit your current for starters and upping the amps slowly till ur quite familiar w/ ur setup. as you start to increase the output start paying close attention to the motor and the amount of heat its generating. if ur motor is a DD and as you start approaching higher temps you may want to consider venting the motor and/or upgrading the phase wires. LOTS of info here on those upgrades so ur covered there as well. if geared, drop the current back down or upgrade to composite and/or metal gears or ur likely to end up w/ PB gears. lastly, post pics when done. cheers

 

[shorza]

Cheers, I should have mentioned my motor/controller setup.

I will be running a 9c 9x7 (unmodded so far) from a Lyen 12FET Infideon controller. I'll be restricting the amps to 25 or 30 and slowly build it up and see how the motor goes.

Thanks again for your help, I should do a full build write up once all my parts come in... and I decide what bike to put it on.

 

[spinningmagnets]

I am a big fan of the XT60 connectors. The pins/sockets are the 3.5mm, and I believe they are rated for 60A continuous and 95A peak. They are very easy to solder wires onto, I use 12ga, but I'm told 10ga fits just fine with no added fiddling. (PS, the pics shows the y-connectors using 14ga, Ive never tried them so I don't know for sure)

Heres a tip: when soldering wires onto the XT60's, mate the male/females together. On about one out of ten solderings, I left the soldering iron on a bit too long, and one of the pins 'drooped' a hair, making it hard to plug in. If soldering with them mated to keep pins in alignment, never had a problem since. I use a 100W soldering iron with a fat tip. Does the job very fast, which is good, because 5 seconds later, the entire piece is so hot I have to set it down (5 seconds after Ive removed the iron, the heat spreads out)

I prefer the 5mm heat shrink to cover the solder shanks, but 6mm will work if you're soldering on a short wire and don't want an accidental shrink-up in the wrong spot.

Even if you decide to use a beefier connector at the power junction of all the packs (4mm, 5mm pins), I guarantee the XT60's are perfect for the individual battery connectors.
4mm pins: http://hobbyking.com/hobbyking/store/uh_viewItem.asp?idProduct=9283
5mm pins: http://hobbyking.com/hobbyking/store/uh_viewItem.asp?idProduct=9194
5.5mm (no housings) http://hobbyking.com/hobbyking/store/uh_viewItem.asp?idProduct=9763

 

[shorza]

Great tips!
I guess with the plugs mated, the heat from the soldering iron is dissipated across both plugs, so won't heat up as quick.
I think I'll have to make up the Y cords myself using 10 gauge wire and 5mm heat shrink.

 

[spinningmagnets]

5mm heat-shrink will not fit 10ga wire, not sure yet about 6mm either. I have assorted wire scraps and a selection of all available heat-shrink, I'll report tomorrow on the correct size to order for 10ga wire (I'm at work right now...Shhhh!).

If anyone is ordering ANYthing from Hobby King, check how much weight can be added in grams before it bumps you into the next higher shipping cost. Heat-shrink is something like $0.25 per meter (3-ish feet), dirt cheap, and so light its only a few grams per meter (add some to every order).

It may be difficult to get two 10ga wire ends soldered onto an XT60 shank-socket, a single stripped 10ga fits perfect, you may have to trim some strands if doubling up. 10ga will work fine for the serial connector set, but for parallel it will be crowded at the single leg of the "Y" unless you use a larger connector socket (XT60's at the battery ends, jumbo "X"mm plug at the controller end).

 

[shorza]

I think I'll order the parallel set already made up. It doesn't matter too much that they are 14 gauge as they won't have the high current that the serial connections and wires will.
Anyone know what heat shrink i should buy for the 10 gauge? 6mm? Will 10mm be too big?

 

[spinningmagnets]

I was suprised to find I don't have any 10ga scraps. 5mm works well to cover a single 12ga wire, and I have used local 3/16" [4.8mm] in a pinch (waiting for China). The fatter black wire is 8ga, and 6mm just fits it. 1/4" [6.4mm] will shrink enough to work on 8ga, so I'm going to guess 6mm will be perfect for 10ga wire.

Two 12ga wire ends will just barely fit in 1/4" (when making a Y with two wire ends in one socket).