Semi-permanent sealing of battery tube


#1

I am considering sealing my battery tubes semi-permanently, with hot glue (or other). I would use a connector (similar to the one I use for my tether) to connect the batteries to the ROV. It would then be disconnected from the ROV and plugged into the charger.

Pros:

  • Less likely to leak (from stray cat hair. or your own legit cat’s hair) This is the big one for me as I have lost a number of batteries to salt water. If the water gets under the positive end of the battery, it is hard to wash all the corrosion out and it slowly kills the battery, dropping it voltage below the minimum.
  • No battle to close battery tubes (though this is solved I hear)
  • More streamlined battery routine (?)

Cons:

  • Getting into the tube, for any reason, will require heating up the endcap with the heat gun. Which will take time, is likely messy and possibly problematic.
  • It is possible the connector could leak. (though the poly fuse(s) can stop a short better than if the water is inside the tube)

Am I mad?

This is where you chime in with “yes! And here is why!”


#2

I use a disconnect for my battery tubes. It makes things a lot simpler to do maintenance, etc… Concerning sealing the battery tubes and charging the batteries in the sealed tubes, I would be concerned about the fact that the batteries heat up a little when being charged. How is the excess heat going to affect the battery tubes and such.


#3

If you go ahead with your sealed battery tubes and quick disconnect, you might want to consider building a second set of battery tubes & batteries so that you can have a spare set charged and ready to go at all times.


#4

I decided to try it out on one of the battery tubes. It occurred to me after, that I did it wrong. This set up doesn’t make it hard to replace a battery, it makes it impossible, without breaking stuff. oops. I have figured out a way to make it better next time. Hooray for learning!


#5

Darcy,

I’m following right along with this concept. It would make my life much easier. Which charger were you going to use with this? I would just be concerned about charging the battery cells evenly.


#6

I am using 4 wires. One for each junction. This way you can charge the batteries the same as if they were separate. The charger only sees the voltage across the wires that it has connected. So to charge the ‘bottom’ (in reference to my excellent drawing above. Using the very best Eric Stackpole technology) The black wire is neg and the blue wire is pos. For the next battery the blue wire is neg and
the purple wire is pos, etc.

I will be using the same chargers as before (since they are all I have right now) and making a fake battery drop in replacement. Working on that right now actually! :smile:

I will post more pictures as i go.


#7

It works! Hooray!
Lets just hope it does not leak. :smiley:


#8

Looks interesting, where did you get the waterproof connectors?


#9

Here is a link to the search on dx.com that shows them. It was tricky to figure out what they were called! :smiley:
http://www.dx.com/s/Copper+Core+Waterproof+Connector


#10

You da man! Thanks

Owen


#11

I updated the diagram to explain the way the batteries are being charged in the second last picture.

As a precaution, I only used one charge space from each charger. When I checked with a volt meter, the two side by side bays seemed to not be isolated. I suspect I am not completely correct since that would not be acceptable for charging, but I didn’t want to find risk having my batteries short out. :open_mouth:

Also I just noticed tat the orientation of the batteries is the opposite of normal. It is correct, but I would (and did) have the positive end near the hot glue cap, just like a normal battery tube.