Thread: Battery question for livescope

I would use a deep cycle battery for what your doing.
Deep cycle batteries are designed to deliver relatively low amperage output for an extended period of time. A cranking battery is designed to deliver high amperage for a short period of time to start the motor.

I don't know how much juice your unit pulls, but the Livescope system pulls 4amps ... so I wouldn't skimp on battery size if you can help it. And yes, as Lowe Rider says ... use a deep cycle battery.

My buddy that has a Livescope has his on a dedicated battery (just because it does pull so much juice) !!

You'll be deep cycling the battery, so... deep cycle it is.

A long day's fishing with LS+head is about 40 Ah!

I run a 50 Ah lithium, lasts almost 2 whole days with 102sv + GLS10. I started out using a wheelchair-type AGM 35Ah that worked well *, but it doesn't quite make a whole day - the LS sucks it right down by the afternoon unless you were diligent about turning it off when not at the bow.

* my units are connected directly to the battery with no extensions to the power cords. My experiences and opinion only. Yes, I'm an EE.

jawjatec what name battery are you using. I checked on line for LI batteries and 12 v 50A run from 70 to 500 dollars. what is the difference?
"gene"

Lithium seem very expensive from what I have found and right now can’t even think about spending 500 for a battery..... what kind of run time on just a normal everyday trolling motor battery? I was thinking of replacing my old (2yr) trolling motor battery with a larger one and using old battery up front for the livescope for now. What’s your thought on that?

Originally Posted by PawPaw "gene"

jawjatec what name battery are you using. I checked on line for LI batteries and 12 v 50A run from 70 to 500 dollars. what is the difference?
"gene"

I am using an Ionic brand of 50 Ah capacity. It is only 15 lbs. It cost around $700; anything for $70 is not going to be a valid choice. Yes they are expensive, but are the lightest you can get. 5 year warranty.

I originally got it to run a 46 lb trolling motor on my kayak (NuCanoe F12) because of weight. I have rheumatoid arthritis in my elbows and can't paddle like I used to. I was using a 35 Ah Duracell Ultra AGM deep cycle wheelchair/scooter battery that weighed almost 40 lbs. So I got almost twice the power for less than half the weight.

Yesterday I used the 35 Ah scooter battery to run my Livescope + 102sv from dawn until 2:30 PM and it was only down to 11.9V when I quit. I've actually never run it all the way down, but I got it as low as 11.5V one long day. System worked perfectly.

Lithium Pro, Ionic, and a few others sure look the same, made in China, and LiFePO4 cells are not cheap. Trade sanctions have made the price go up recently. But if weight is your primary concern, there is no better option. IMO only, and it is a professional opinion, or was until I retired early to go fishing. Ga Tech EE "89.

Originally Posted by Jiggin john

Lithium seem very expensive from what I have found and right now can’t even think about spending 500 for a battery..... what kind of run time on just a normal everyday trolling motor battery? I was thinking of replacing my old (2yr) trolling motor battery with a larger one and using old battery up front for the livescope for now. What’s your thought on that?

I see no reason not to try it. Everyone's needs and weight considerations are different, as are their wallet contents, lol.

As for your run time question: batteries are rated in terms of the Amp-hour unit. (We capitalize Amp because it is a man's name: Ampere, but not hour). Amps is a current unit. Amp-hour is different. Essentially, 1 Ah means it supplied one Amp of current for one hour (and still maintained 12V or thereabouts). I have not measured the actual current of my setup (102sv + GLS10) but my educated guess is it is around 4-5 Amps, close enough. So, in theory (ball park theory, not actual EE theory, don't want to glaze your eyes over or put you to snoring), a 50 Ah battery should run my setup about 10 hours. Add a grain of salt because battery makes sometimes fudge the numbers. I rarely fish all day, I usually hit the lake while still dark and fish until 1-2 PM.

Any good brand of Lithium battery, Battle Born, Lithium Pro, Relion, Ionic, is going to cost well north of $600 in a 50 Ah size. I went with the Ionic as they were a new company, used prismatic cells (as opposed to having a load of 18650 cells inside all strapped together), and were on sale.

Note: as opposed to a lead-acid battery, all lithium batteries have a circuit called a BMS (battery management system) which sits between the actual lithium cells and the posts of the battery. That is because LiFePO4 batteries are dangerous if overcharged, shorted out, or run too low. Unfortunately, there is no standard for these BMS systems, so the charging profile and voltages can vary quite a bit between brands. The Ionic specifies 14.4V max during absorption pahse, and the Noco G7200 puts out 14.6V in "Lithium" mode (as if there is a standard - there ain't) so I use the "AGM" setting which puts out 14.4V. You have to compare apples to apples and that is not always easy to do. Most of the folks selling these batteries are not even engineers, and mix up the terms, and don't know what they are blathering about most of the time. They are just businessmen selling a Chinese product, and don't really know bupkus about it. Fact.

EDIT: Forgot to add: Lithium batteries do not like sub-freezing temps, so if you are way up yonder in yankee land, buyer beware. The lake is usually 32F or higher, or it wouldn't be a lake, more like a hockey rink. Check the temp specs before you buy. My boat sits in a cozy garage when I'm not fishing, but I do fish 12 months of the year. Not a factor in GA, no.