2nd (additional) battery
-> 4x4 Tech

#1: 2nd (additional) battery Author: SpoilerFJ84Location: Tucson PostPosted: Sun Feb 04, 2018 10:16 am
    ----
Hey everyone. As such with Punxsutawney Phil, I make my annual appearance.

I've gotten into my "slow" season and am now again able to focus on mods I've wanted to do for years to the ol' FJ. Going through some boxes in the garage I found a bunch of switches and aux USB ports I bought years ago that reminded me at one time I wanted to install offroad lighting and cellphone/tablet charging ports.

I figured I would just get a 2nd battery and fab a bracket for it to run all the aftermarket electronics I plan on doing, so my questions are as follows:

1. Do I need a 2nd battery?
2. If I do, what kind/type/size is recommended to run a few USB charging ports and front and rear aux LED lighting

...think that was it. =)

#2: Re: 2nd (additional) battery Author: zzmikeyLocation: Ahwatukee, AZ PostPosted: Sun Feb 04, 2018 11:13 am
    ----
I have second battery, sylonoid, controller, bracket, etc... If you want to take a look at it all

#3: Re: 2nd (additional) battery Author: JimbolioLocation: Tucson PostPosted: Sun Feb 04, 2018 8:39 pm
    ----
Happy to show you mine as well down here in Tucson.

#4: Re: 2nd (additional) battery Author: calichaos PostPosted: Mon Feb 05, 2018 7:19 am
    ----
SpoilerFJ84 wrote:
...
I figured I would just get a 2nd battery and fab a bracket for it to run all the aftermarket electronics I plan on doing, so my questions are as follows:

1. Do I need a 2nd battery?
2. If I do, what kind/type/size is recommended to run a few USB charging ports and front and rear aux LED lighting

...think that was it. =)


the questions are reversed

2)
What kind/type/size of second battery would be required to run a few USB charging ports, and front / rear aux LED lighting


None ---- Unless you plan on running those items for extended (several hours at a time) without running the engine.

1) do I need a second battery?

No; unless there is more your not telling about your use case.

#5: Re: 2nd (additional) battery Author: MasadaLocation: Glendale, AZ PostPosted: Wed Feb 07, 2018 8:50 pm
    ----
Is there a detailed write up on adding a 2nd battery, I know I want to do this to my FJ but would really like to know more about what needed and more importantly why it's needed.

I've seen many done with an automatic charging relay and the need for a fuse from the starting battery to the aux battery but can't understand why and how large.

#6: Re: 2nd (additional) battery Author: BellyDoc PostPosted: Wed Feb 07, 2018 10:49 pm
    ----
The main reason to run asecond battery is to have the capacity to deeply discharge battery power and still be able to start the engine and then drive away/recharge.

The unfortunate properties of battery discharge make it so that when there are dual batteries hooked together in simple parallel, one sucks the life out of the other prematurely and so a form of "battery isolation" is required. Dual battery isolator kits are available from multiple vendors. These allow one alternator to charge two batteries, one of which supplies the starter and whatever low draw accessories you might want to run, or at least those things you won't likely need while the engine is off. The secondary runs high draw accessories such as a winch, a powerful light system or whatever you think you'll be using extensively while the engine is off.

#7: Re: 2nd (additional) battery Author: MasadaLocation: Glendale, AZ PostPosted: Thu Feb 08, 2018 7:46 am
    ----
My plan is to run a blue sea ACR (automatic charge relay) between the crank battery and the aux battery with a switch in the cab that can switch between each battery and has a feature that will isolates one batter from the other until the main battery is fully charged. So if i'm understanding it correctly, it shouldn't drain the main battery.

My plan is to have several lights, winch, CB and air compressor hooked up to the aux battery

#8: Re: 2nd (additional) battery Author: JimbolioLocation: Tucson PostPosted: Thu Feb 08, 2018 1:49 pm
    ----
My National Luna Intelligent controller is based on a time period of running at a certain voltage (13.4+ I believe). Then it will click over and start charging the second battery until it is up to capacity. Then it sends a maintenance charge to both. That's some hard thinking there that would not be easy to replicate with a solenoid and fuses. But I suppose you could buy one of these and set it to 5 minutes, and when it dings, switch over to battery 2.



-> 4x4 Tech

All times are GMT - 7 Hours

Page 1 of 1