fish finder battery

1960 yellowboat · Feb 7, 2020

Just a thought/
As most fish finders run off 12 volts, where to put the battery can be a challenge, especially if it's a lead/acid type.
Why not just use a 12 volt battery pack originally made for a cordless drill?
Either ni cad or Li Ion.
They seem to be infinately rechargeable, don't leak, and can be mounted any where and any way.
What's the concensus?

onthewater102 · Feb 8, 2020

Might be some squirley electrical connections to the contacts on one of those batteries, short of cannibalizing a drill or other tool/component for the receiver side connections I don't see how you could do it cleanly or what you'd gain. Those batteries don't have the amp-hour capacity to run a fish finder all day, so other than reusing what you've got already where's the point?

A sealed lead acid battery made for a computer backup works perfectly, is easy to terminate connections on and has sufficient energy capacity to run a fish finder all day.

LDUBS · Feb 8, 2020

Interesting. Seems like you would have to crack open the case and expose the actual battery pack to make the connections. I don't know about capacity of Li Ion batts for a FF. Seems like they last a long time in my drill, but just about everyone is going to know more about this than I do.

onthewater102 · Feb 8, 2020

Looking quickly I see 12v drill batteries with amp/hour ratings of 3hrs +/-...I have a 10 A/H battery for my humminbird 898 unit and it will last a day of fishing, the 6 A/H battery I tried before it would not as the voltage drops over time to the point it won't work even though the battery isn't anywhere near discharged. A 3 A/H wouldn't power anything for very long.

maintenanceguy · Feb 8, 2020

The down side of a drill battery is finding a compatible socket to plug into. If they made the fish finder with that socket, it would work great. Could eliminate one set of wires completely. A truly portable fish finder - just hang the transducer off the side of the boat. That is a good idea.

If you want light weight and portable, try something like this: https://www.amazon.com/Powersonic-Sealed-Rechargeable-Battery-Security/dp/B007Z462S8

Read the specs on the fish finder to see how many amps it uses. Multiply that by the hours you want to use it. Amps x Hours = Amp Hours or AH or Ah. Batteries will list their Ah.