New battery time

[Glenn-BJ74]

Marine starting batteries are built to take a pounding (e.g. speedboats) and they have thicker plates (that provide lower but longer output),- as a result they do not produce as much instantaneous current as a starting battery (need thinner plates to do that) - a 6bt needs a Group 31 starting battery.

I don't leave smart chargers on during high ambient temperatures (over 75F), unless it has temperature compensation, which most do not have - It will overcharge/boil the battery. My experience.

Temperature Compensated Battery Charging

 

[Enigma]

Truck has been sitting in the driveway with the fridge running since Monday (just moved it off the lawn and onto the driveway Tuesday) and the accessory battery is reading 11.76 and starting battery 12.5. No solar panel hooked up.

Tested again just now. Truck has not moved since this last post, fridge running at -1 with a few beers in it, 50 watt panel has been connected since last week and basking in the sun on the roof. Acc battery reading 12.05 and starting battery at 12.5.

I was thinking I needed a larger panel, and might still if I really need that battery to charge fully while under load, but for now it's working as intended. Fresh battery sure makes a difference! I don't recall with the old battery it running as long as this.

 

[Wheelingnoob]

My battery decided it had enough of cranking the Cummins over in the Nexus line yesterday.......fortunantly the guards though the swap was cool and helped me push it into secondary.

 

[Granite Grinder]

My battery decided it had enough of cranking the Cummins over in the Nexus line yesterday.......fortunantly the guards though the swap was cool and helped me push it into secondary.

If you were at the truck crossing, one of the guards is a cruiser head, his Dad got him hooked

 

[Wheelingnoob]

If you were at the truck crossing, one of the guards is a cruiser head, his Dad got him hooked

I was headed south, not sure if he was a cruiser guy but knew what the truck was.

 

[Enigma]

Perhaps I should do these tests at night. Grabbed some beers out of the fridge last night at 9 and the red light was flashing and it had warmed up to 5 degrees. Didn't have time to take a voltage reading as we were heading off to the fireworks.
Checked the fridge just now, back to 0 and the power setting is set to LO which is ARB's recommended setting for an aux battery connection. It should turn off at 10.1V and restart at 11.1V. The reading I took just was bouncing between 11.2 and 11.8; I assume from the compressor cycling as the sun is charging through the panel.

 

[Output Shaft]

the accessory battery is reading 11.76

Say goodbye to your battery.

 

[Wheelingnoob]

Yeah I was going to say, at that low a voltage your killing your battery. Deep cycles are more resilient but your basically completely killing your battery every night. It's not going to last long doing that.

 

[Enigma]

Interesting. Well I'll just plug it into shore power for the time being and try some tests when I get a larger panel.

 

[Output Shaft]

From my experience with the older ARB swing motor fridge, a single 75watt solar panel directly aimed at the sun, tracking it all day long on a clear day, just barely had enough power to run the fridge 24 hrs/day with the inside temp set to 42°.

 

[Glenn-BJ74]

On my last truck - my 80 watt panels provided surplus power to keep my Engel fridge cold and keep both batteries fully charged on cloudy days.
Maybe the difference is the Morningstar SunSaver MPPT charge controller I was using?
It can generated power when the panel voltage is above 14.5. Most other (non-MMPT) charge controllers can only harvest power when the cells are between 10-14.5 volts, but cells can maximize usable power to about 18 volts, which can only be harvested by a Maximum Power Point Tracking charger.There are some Chinese MPPT chargers ones that are junk, so I went a reputable US company - Morningstar.

 

[Output Shaft]

That's good info to know. I was using the cheapo Morningstar SunSaver old style controller back then. I've had my eyes on those MPPT regulators. Guess I got my answer right there. Thanks.

My previous comment of "barely" implied that I didn't have all that much left over solar capacity after fully charging the batteries. It could keep up, but needed sunny days and to be actively pointed at the sun to do so.

 

[Enigma]

While looking for something else, I stumbled across my original battery replacement thread from January 2009. So 7 years of fairly severe abuse on both of them, with the starter still doing well.

 

[Glenn-BJ74]

How many kms in those 7 years?

 

[Enigma]

How many kms in those 7 years?

Uhh,,,not a lot. I think I'm only at around 140,000 km right now (not including any adjustments from 31's to 315's) and and 65,000 from when I bought it in '08.

 

[wrongway around]

Less is more , more or less. I get new optima yellow tops for $130 each but the guy is hit or miss , mostly miss though ? I have a call into him for you I'll send you his number when and if I hear from him. I run two batteries for my house batteries one on top of jasons passenger side tc slider. And yes huge difference with the MPPT I think . I've got two rv setups and none issue so far , mind you they are supported with 6volt Trojans.

 

[Wheelingnoob]

I ended up getting two group 31 batteries today with the non automotive threaded posts. All my lines connected and after a bit of modifying the battery boxes to fit I now have a combined 2000cca.

I went to the Interstate battery in Port Kells and got there econo power brand for $49 each. Yes they are remaned on site but the guts are all new and it's got a 3month replacement warranty. This will get me through the summer and give me time to make sure I have no issues before I drop 5-600 on batteries.