Charging Battery during three week long road trip.

I've done a lot of off road stuff to out of the way places here in Australia. I tried various solutions to keep lights, fridges, etc running. One of them was portable AGM batteries which you could recharge when you ran your truck.

In the end I went for what I believe to be the most effective solution solution - a dual battery system that sits under the hood of your truck. The batteries you put under there tend to have higher amp hours and are not being charged using your alternator as a portable AGM would be.

Yes, initial installation requires a bit more money but it works so well. They can be set up to take portable solar panels if you intend to stop in one place a for a few days.

Holden4th wrote: ↑

Mon May 21, 2018 1:52 am

are not being charged using your alternator as a portable AGM would be.

Eh? then how are they charged?

To power my cpap while trailer camping one of the methods I used to use involved a lead acid battery I kept strapped in to the back of the bed of my truck. I made up a harness to connect it to a connector in the front of my trailer that powered an outlet in the bedroom separate from electrical system of the trailer. I did this because the trailer batteries would get drawn down voltage wise by other things like the furnace during the night and kick off my cpap. I also made a jumper harness that went from the 7 pin trailer connector on my truck to the spare battery. I would hook this harness up when I was using the truck so that the truck electrical system would charge the spare battery. Current flow to the battery was somewhat limited by wiring, but I still always managed to keep the battery charged enough there wasn't any issues. Now my camping involves a large fifth wheel with a big battery bank and 10 100 watt solar solar panels on the roof so I can easily keep the whole trailer powered through an inverter 24 hours a day and just plug things into the ac outlets like when I'm home. Seems almost wrong to call it camping now. I use the need for the bipap to justify the fifth wheel.

A slight update, my original plan of using my cpap battery in place of my car battery to charge it has hit a snag. My deep cycle battery has opposite battery terminal locations compared to my car. The currently installed cables are unable to reach due to this. On to a more complicated solution!

bryanftc wrote: ↑

Mon Jun 04, 2018 8:48 pm

A slight update, my original plan of using my cpap battery in place of my car battery to charge it has hit a snag. My deep cycle battery has opposite battery terminal locations compared to my car. The currently installed cables are unable to reach due to this. On to a more complicated solution!

You got lucky, that was a poor solution. Jim

Goofproof wrote: ↑

Mon Jun 04, 2018 9:54 pm

bryanftc wrote: ↑

Mon Jun 04, 2018 8:48 pm

A slight update, my original plan of using my cpap battery in place of my car battery to charge it has hit a snag. My deep cycle battery has opposite battery terminal locations compared to my car. The currently installed cables are unable to reach due to this. On to a more complicated solution!

You got lucky, that was a poor solution. Jim

Lucky?

bryanftc wrote: ↑

Tue Jun 05, 2018 7:51 am

Goofproof wrote: ↑

Mon Jun 04, 2018 9:54 pm

bryanftc wrote: ↑

Mon Jun 04, 2018 8:48 pm

A slight update, my original plan of using my cpap battery in place of my car battery to charge it has hit a snag. My deep cycle battery has opposite battery terminal locations compared to my car. The currently installed cables are unable to reach due to this. On to a more complicated solution!

You got lucky, that was a poor solution. Jim

Lucky?

Yes! Lucky, There are much better ways to recharge the battery from the auto. Down and dirty, use the Cigar Lighter Plug with a properly rated circuit breaker in series with the positive wire. Better Hook 10 gauge wiring to battery in auto (Fused at 30 amp with circuit breaker) to second battery. Best use Better and hook up a relay after the 30 amp circuit breaker to kill the power to the second battery circuit.

WARNING: Nothing is Foolproof to a determined Fool! Safety First always. Jim

bryanftc wrote: ↑

Fri May 18, 2018 8:05 pm

Jas_williams wrote: ↑

Thu May 17, 2018 11:27 pm

Look at getting a split charge relay fitted to your truck to charge the AGM battery when moving and solar panels to supplement when stationary should keep you going with no issues.

Take a look at this link for ideas

viewtopic/t114012/Choosing-a-Battery.html


Jason

Thank you for taking the time to respond to my post. I think I'm going to avoid that solution at this time, if I find myself having to take an extended camping trip in the future I will bite the bullet and invest in the relay and solar panels.

This past weekend I went camping with my cpap and a Motomaster Eliminator 1600A/600W battery booster and portable power pack fully charged up, the first night I hooked up the cpap and a fan and fell asleep for about 1 hour and was awakened with this loud alarm going off on my eliminator!!! The battery was dead, 3 nights without my cpap of fan!! Such a disappointment!! Not really sure what went wrong but charging it up again and will try it at home without the fan!!

hardtime0022 wrote: ↑

Sun Aug 23, 2020 8:46 pm

This past weekend I went camping with my cpap and a Motomaster Eliminator 1600A/600W battery booster and portable power pack fully charged up, the first night I hooked up the cpap and a fan and fell asleep for about 1 hour and was awakened with this loud alarm going off on my eliminator!!! The battery was dead, 3 nights without my cpap of fan!! Such a disappointment!! Not really sure what went wrong but charging it up again and will try it at home without the fan!!

Were you running the humidifier?
Were you running a heated hose?
Did you plug your CPAP into the AC outlet on the power station?


The Eliminator 1600 has a capacity of 28 Amp hours. A ResMed AS 10 (11CM, DC, no humidifier, no heated hose) will draw about 1 amp.

So it will last about 28 hours.

You should NOT let the battery fully discharge, so two full nights should be OK.

A 50 watt table fan will draw about 4 amps.

It sure sounds like you were running on AC, with humidifier, and AC fan, an hour sounds about right.

hardtime0022 wrote: ↑

Tue Jun 05, 2018 10:19 am

Not really sure what went wrong but charging it up again and will try it at home without the fan!!

Prob should have done that first. Always, always, experiment at home at a time and place where if things don't go as planned you can re-group, recover, and re-plan.

Now I'm gonna guess cuz you didn't say but it sounds like you didn't research this battery booster or if you used AC for both the fan and the cpap? Amazon had 4 ratings of 4 all at 1 star. Always, always get the DC cord for your cpap and use DC (battery) for the longer time of use. Converting DC to AC then back to DC always depletes the battery sooner.

As mentioned already do not use heated hose or heat for humidity if/when you want to extend the battery life. For humidity just turn the heat off and allow the air to "passover" the water.