Twice the Battery Life with Adjusting Lowrance Screen Brightness?

Measuring actual amp draw and voltage of various Lowrance units using 12v23Ah Dakota Lithium as power source

I have been doing a lot of testing with Lithium batteries these days, both on the ice and off trying to find the best way to calculate exact run time based on devices connected. I am doing this not only for my own benefit, but also because I continually see many asking what is needed to run Lowrance Active Target in their system power-wise, both on the water and in portable ice applications. Well, I am getting better and better at determining a way to calculate run-times, but I wanted to address a statement that I read the other day as to is it fact or myth, namely that “I can get twice the life out of the battery by simply turning down the brightness half-way”.

Changing the brightness of Lowrance screen can make a difference in power drawn

Well, the answer with a HDS-9 Live unit is yes, one can get nearly twice the hours of use by  decreasing the brightness 50%.

This is not possible with a HDS-7 Live unit as the screen is smaller and the screen brightness is not as big of a power draw influence as compared to the larger screen. With a HDS-12 and HDS-16, the “core” operating system power draw is higher and because of that, one is also not able to achieve the “twice the battery life” goal, even with the screen brightness turned all the way down.

Power draw for HDS-12 and HDS-16 Live units have a noticably different pattern than the smaller units

But regardless, the main point is that adjusting the brightness of the screen can make a big difference with battery life, particularly with the that first “click”, as that makes the largest impact of power consumed regardless of the screen size.