10.56 Volts

[CPT Davenport]

After camping in 114 degree temps, my fridge was working overtime. This morning I woke up to the battery sitting at 10.56v! everything still works and the fridge is running and ice cold.


How can this be? Doesn't everything in the camper require at least 12v?

 

[ckent323]

Make sure you fully recharge it right away before drawing it back down again. 10.56 V is effectively a dead battery - 100% depth of discharge.

Most electrical devices will run on low voltage but will pull more current which can damage them.

Discharging a lead acid battery that much risks damage to the battery and reduction of its service life. That written if you don't do this more than a few times it may not make a significant reduction in usable life.

https://www.pveducation.org/pvcdrom/lead-acid-batteries/characteristics-of-lead-acid-batteries

 

[CPT Davenport]

Thanks Craig,

I have shut everything down in the camper and the battery is charging as we speak. This was too close for comfort. I'm either going to increase my bank to 200ah or bite the bullet, pull off and rewire the camper, and install my DC/DC charger.

 

[Vic Harder]

Also, if the fridge and fan were running at the time you saw 10.56 volts, the battery was not "resting". With no load, it might well have been at 12.2v (50%) or higher. SOC readings are way more informative than voltage.

 

[CPT Davenport]

Also, if the fridge and fan were running at the time you saw 10.56 volts, the battery was not "resting". With no load, it might well have been at 12.2v (50%) or higher. SOC readings are way more informative than voltage.

Right you are Vic. I need that shunt asap! Feel like I'm flying blind without it after this experience.

 

[ckent323]

"Right you are Vic. I need that shunt asap! Feel like I'm flying blind without it after this experience."

Three thumbs up on that!


Vic is spot on.


Craig


Vic is spot on.