Connections when riding ebike with batteries in a backpack?

[Sacman]

Does anybody ride their ebike with LiPo batteries in a backpack?
I tried it for the first time the other day and I kept having problems with the battery connections coming apart.

I have 12-gauge wires coming from my controller running up my seatpost and ending with Anderson connectors. And then l have Anderson connectors with 12-gauge wires leading from my seat to the batteries in my backpack. The Anderson connectors are crimpped and soldered on properly. Sounds strange but the Anderson connectors pull apart fairly easily with thick 12-gauge wires attached to them. I've had to sit on the wire going to my backpack to prevent it from moving. I guess I could just wrap the Anderson's with electrical tape to keep them together but does anyone know a better way to keep the connectors from pulling apart?

 

[miuan]

No problems so far with Turnigy 12AWG silicone wire and HXT 4mm bullets.

 

[voicecoils]

The retainer / joiners that Powerwerx sells are pretty ideal for holding Anderson Powerpole connections together.

I find that the Powerpole contacts have decent connection force when crimped with the proper tool. But, if the shape is not perfect, the connection will be loose.

Otherwise you could change to the Anderson SB50 which requires much more force to make / break the connection.

 

[neptronix]

Solder rather than crimp helps..
The 1 pair of Andersons i encountered had the coming apart problem too. Dumped them in short order!

4mm bullets are solid. Don't snap into place, and have a pretty tight fit. Can't recommend them strongly enough.

But for your current setup, maybe you have some stress on the connectors.. they can't tolerate much.. 4mm bullets will, in this case, pull out a little.. the smaller andersons will disconnect entirely.

 

[dogman dan]

Mabe add some extra housings to make a block that takes a bit more pull to disconnect, but still pulls apart fine when you need it to.

 

[itchynackers]

You could tie a rubberband to each end of the connection (just behind each anderson). This keeps compression on the connection, and if you make the rubberband properly, its even re-useable.

 

[adrian_sm]

http://www.powerwerx.com/powerpole-accessories/retention-clips.html

 

[Ypedal]

I use a piece of cardboard, rolled up in a cone shape, taped to the wire inside the backpack, just behind the zipper, so that the andersons cannot be pulled or tugged, they remain connected.

will try to find a picture.. it's a cheap and quick solution..

I do like those anderson plugs tho.. hmm..

 

[Ypedal]

or the even lower tech version..

tape the wire to the pack with a loose loop on top.

:lol:

 

[vintagerider]

just a question about backpack batteries i was considering this also, will a sudden disconnect hurt or damage the controller? as i wanted for off road use, to find a connection that would disconnect upon my ejection from bike in sudden crash or jump gone bad. sorry for newbe question as i have not built any ebike as of yet!

 

[Ypedal]

i've accidentally disconected while at full power plenty of times before.. never blown anything up.. yet..

 

[grindz145]

I actually prefer that the connector pulls out with sufficient force. that being said, I realize the andersons are just too loose as is...

 

[hydro-one]

warning, dont pull the connector out under full power, Im sure i have blown fets this way. |Jumped on, hit full power, stood up and unplugged partially, blew one fet. happened three times.

I use a kevlar wrap (sheath on the wire, highly reccomended!! also i use old political signs to fold around the pack . almost three years now , still have some of my original 20c turnigys in the mix.......thousands of cycles

good luck with that, you will love it , your back might not but oh well soliders carry ninty pounds on thier back

 

[Sacman]

4mm bullets are solid. Don't snap into place, and have a pretty tight fit. Can't recommend them strongly enough.

But for your current setup, maybe you have some stress on the connectors.. they can't tolerate much.. 4mm bullets will, in this case, pull out a little.. the smaller andersons will disconnect entirely.

The only connections that keep falling apart on me are the Andersons by my seat post. The Andersons at my battery (inside the backpack) seem to stay snug and connected. I forgot about trying the 4mm bullet connectors. They do seem to require more force to pull them apart.

http://www.powerwerx.com/powerpole-accessories/retention-clips.html

LRB... I've used Andersons for 4 years and this is the first I've heard of those clips! I might have to get a few and try em.

But for safety I do want the connection to come apart if I yank hard enough (whether intentional or accidental) and these clips appear to hold too strong. I do like the idea of using a rubberband to add compression to the connections but that could get tedious to tie and un-tie each time I get on the bike to ride. It's kind of the same reason why I preffer NOT to just wrap the connector in electrical tape.

 

[miuan]

I forgot about trying the 4mm bullet connectors. They do seem to require more force to pull them apart.

They're pretty good at staying plugged in when needed and still pull out once you force them, without noticeable damage, since there are no pawls or similar wear parts. But be careful with different styles. The HXT 4mm plugs with red protectors that can be bought in 10pc bags are good. The plugs used on cheap 4S hardcases and maybe some other turnigy stuff use softer plastic, and are prone to unplug under repeated shock. It happened to me once with a serial string in a 2P pack and I overdischarged the remaining 1P string severely, nearly lost it. I duct tape them together ever since.

 

[Ypedal]

If they disconnect at the seat post, a piece of velcro around the rube and cable might do the trick, would hold just enough to prevent a pullout but would come un-done if you crash...

 

[Sacman]

If they disconnect at the seat post, a piece of velcro around the rube and cable might do the trick, would hold just enough to prevent a pullout but would come un-done if you crash...

Ahhhhhh....Velcro!
Sounds like a simple and elegant solution to me. I'll give it a try.
Thanks Gaston!

 

[Ypedal]

My cardboard cone method, lasted an entire season and still perfectly ok !

 

[rojitor]

Deans are not easy to get loose, maybe you could try to make a deans to anderson wire.

 

[GrayKard]

LRB... I've used Andersons for 4 years and this is the first I've heard of those clips! I might have to get a few and try em.

But for safety I do want the connection to come apart if I yank hard enough (whether intentional or accidental) and these clips appear to hold too strong. I do like the idea of using a rubberband to add compression to the connections but that could get tedious to tie and un-tie each time I get on the bike to ride. It's kind of the same reason why I preffer NOT to just wrap the connector in electrical tape.

Been using those plastic retainers for a couple of years now. They keep the connections together nicely but if I get separated from the bike one of the pins on the retainer will break and allow the andersons to disconnect.

Gary

 

[FastDemise]

I swapped out all my Deans connectors for the XT-60 connectors. They are actually a bit annoying at times because it takes a lot of pull to separate at times. For a added bonus it does use bullet style connectors.

Just a link for reference
http://www.hobbyking.com/hobbyking/store/uh_viewItem.asp?idProduct=9572