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Battery options for a reverse para-scope. Answered

Hey everyone!
so I'm building a para-scope for the dock at our cottage, except it will be used to peer down into the water and watch the fish.Just need a battery solution other then a 12V sealed lead acid battery that I already have. (hopefully light weight)

1X waterproof camera tested @12 V (maybe 9v? test soon but does not work at 5v)

1x lcd screen tested @ 5-12V

plus some pvc piping and other bits and bobs.....

I have some spare lipos that I can connect in series but a bms would require 12.6v (Less voltage drop?) Ideas?

BMS link ==> https://leeselectronic.com/en/product/16178.html?...

9V battery will not last long enough

Any other ideas that will not cost an arm and a leg?



Jack A Lopez

1 year ago

Does your dock lack electricity? Does the cottage lack electricity?

I guess I am not quite picturing it. Is the dock so far from the cottage that it would be impractical to run an extension cord to the dock, where you could place an AC adapter, for to convert the mains power from the extension cord, to 12 volts, or 5 volts DC, or maybe it's 9 volts, or whatever your little gizmos want?

By the way, do you happen to know how much power your setup uses? Like, how much current (in amperes) the 12 volt (or maybe it is 9 volts? Or 5 volts) supply must supply. I mean, that's kind of the first step for figuring out how big of a battery you need.

Jack A LopezWired_Mist

Answer 1 year ago

At 500 mA = 0.5 A, with a 10 A*hour battery, you could watch fish all day! Almost. I mean, (10 A*hour)/(0.5 A) = 20 hours.

I dunno. How many hours of watching fish, till everyone involved gets bored of watching fish?


That makes me think: watching fish at night might require more millamperes, if the camera includes a light for to illuminate its surroundings. Here, I am naively guessing that you're not sending the camera to a place so deep, it is equally dark during the day and night.

Regarding the battery, I guess the battery you have, the lead brick, is probably about the right size ( in ampere*hours), and about the right voltage (at 12 volts, nominal). You just want something with less mass.

There are instructables on the subject of building batteries, or the so called, "power bank", from Li-ion cells, plus per-fabricated battery manager board.

Although, I am not really an expert at building batteries. I should probably just stand back and let someone who is confident at battery building, answer this question.

By the way here is link to everyone here, who thinks he or she knows how to build a "power bank"... or at least what the Let's make: search for those words returns.



1 year ago

Longer feed wire and keep battery on land.

Why not go traditional and use mirrors?


Answer 1 year ago

Materials looking for a project ;)
But think i might try that just for fun!

Jack A Lopezrickharris

Answer 1 year ago

Use optics? Like lenses, and prisms, and mirrors and stuff? You're thinking of a periscope,


That's spelled with an "i", and no hyphen.

OP is asking about, "para-scope". Obviously a para-scope is just a video camera on the end of a stick.


Jack A Lopez

1 year ago

I looked at the product link you pointed to, and I think that one is a board intended for three 18650 wired in parallel.

Also I think boards for wiring cells in series, often have the word 2S, 3S, 4S, or etc, in the description. Also the capital "S" stands for "series".

Although, from that kind of logic, I would expect the board you pointed to, to have the word, "3P", in its description, with "P" standing for "parallel".

By the way, there is no shame in using a lead-acid brick, as long as it stays above water. As others have pointed out, the battery does not have to go underwater with the camera. All you need is a two wires, to carry DC power to the camera, and those wires can be long, as can the wires delivering signal from the camera.

I think the people who, professionally, put robots underwater,


they call that long cord an umbilical cord, as kind of an analogy to the biological version with the same name.

Also, there is a section of this Wiki article for underwater ROVs, titled "Classification". I was looking for the one that is so simple it is just a camera on a stick. I did not find the phrase, "camera on a stick", but I did find the phrase, " 'eyeball' class", which I am guessing is sort of the same thing as what you're building, in terms of function. I.e. you just stick it underwater, and use it to look at stuff.