Backpack range extender! (Parallel)

Hey guys! So I’m new to the esk8 scene but I’ve ordered the new backfire g3 and at some point, I would want to build in a range extender. Here’s my idea, thoughts and advice appreciated:

G3 battery: 50.4v 12s 346Wh

My idea is to make and connect this xt90 loop key (https://www.electric-skateboard.builders/t/how-to-anti-spark-xt-90s-loop-key/204) in parallel with the normal battery and have it sit on the outside of the board, then put the second battery (same type) in my backpack and connect it to an xt90 male end to plug into the loop key whenever I want to use it. Is this do-able? Also, are the xt90 connectors pull to disconnect (if not what else could I use)? That way if I fall, I don’t yank on the cables and gut the electronics. Also, this setup would allow me to build in additional batteries at any time.

My .02 I think you need to do a lot more reading before you do some damage. Loop keys are wired in series, never parallel. If you plug a battery into a loop key port you willl at least fry your board, if not start a raging fire. If you wire a loop key in parallel you will definitley start a fire.

It is possible to do what you want but if you are not absolutely sure of what you are doing, better stay away from these kinds of mods.

Stay safe friend,

2 Likes

I think I see what you mean there (the battery would be connected end to end with a true loop key setup like I imagined). What if I connected a fake loop key in parallel? Like, it would be a parallel connection that is open, with a fake cap, which I could then remove and plug the backpack battery cable into to close the parallel connection.

I could make a silicone cap or smth to try to prevent shorts from the loop key when the second battery isn’t plugged in

If you want to use an xt60 of xt90 connector to plug in the extender AND also have a loopkey, they need to be separate AND use different genders/sizes for each. If you or someone else happens to miss plug your loop key it will destroy your board so make it so its impossible to mis-plug it…

1 Like

Well I was thinking the loop key would be a fake loop key. Just a silicone cap to prevent water or any stray metal from connecting the two leads. As long as it’s plugged in, the connection should be safely secure from exterior elements. Then, when I want to plug in, I just unplug the ‘fake loop key’ silicon cap from the parallel connected xt90 and plug in my connector cable. Any better ideas for a safe and easy parallel connection?

That sounds reasonable as you’ll want a higher amp connection.

But that connection is the easy part. You need to be concerned with current limiting/how youre going to handle the different battery voltages… Not my area of expertise.

Pambalos

1m

I was thinking I’d just buy the exact same battery. That would make it hassle free to think about all that stuff yeah? I was reading and watching people have issues when adding batteries of different setups. So I was thinking of adding batteries of the exact same setup and type.

@Pambalos Just remember that you can’t plug batteries in parallel if their voltages are different (they will even themselves out with very high amps). I did a project like this a few months ago. I had a switch to decide where the power was coming from between the inboard batteries and my backpack batteries. This way you never have them powered at the same time