Do I need a second battery?

[Lewis&Clark]

This weekend, I'm adding several A/C ports in my '08 Ltd. The single port included in the car is in the most awkwardly stupid place it could be (inside the center console), and one isn't enough.

I'm still drawing up the plans on how to wire this, but the plan is to put two in the back seat (probably mounted on the backside of the center console, below the air vents and behind where the garbage bag would be if I actually used that holder.

Also plan to add one in the trunk/cargo area, and one under the globe box for the front passenger.

None of them would ever run anything more power hungry than a 15" laptop. No fridge. No heavy duty equipment. It's primarily for laptops and charging mobile devices for passengers. However, it is conceivable that I could have several people in the car all using the power sockets at the same time.

(Notwithstanding the one in the cargo/trunk area, which would be used only occasionally and not likely when anything else in the car is in use.)


Should I be adding a second battery to the car to accommodate this scenario? I would think the current power supply while the car is running is more than sufficient since I won't be using any big equipment like a fridge, but thought I'd ask y'all what you think.


dt

 

[dchild]

If you will only ever use the power while the engine is running, no need for a second battery as the load will be on your alternator.

You may need a bigger inverter if you will have several people using laptops at once.

 

[Lewis&Clark]

If you will only ever use the power while the engine is running, no need for a second battery as the load will be on your alternator.

You may need a bigger inverter if you will have several people using laptops at once.

Thanks.

So stupid question, cause as I mentioned, I'm still working out how to do this and haven't sat down with my electrical engineer friend (Friday). If the car already ships from the factory with a 115V AC port, it would seem logica that the car already has an inverter to convert DC into AC. Is it therefore necessary to add another inverter?

 

[m85476585]

Thanks.

So stupid question, cause as I mentioned, I'm still working out how to do this and haven't sat down with my electrical engineer friend (Friday). If the car already ships from the factory with a 115V AC port, it would seem logica that the car already has an inverter to convert DC into AC. Is it therefore necessary to add another inverter?

The stock inverter in the 4th gens is only good for 100 watts, so you'll probably want a bigger one for anything more than one laptop at a time. It is enough for one laptop or most smaller things like cell phone chargers. If you add a bigger inverter, you'll probably need to run a new 12v circuit for it with bigger wiring if the existing circuit only has a 10A fuse (likely).

 

[alia176]

This weekend, I'm adding several A/C ports in my '08 Ltd. The single port included in the car is in the most awkwardly stupid place it could be (inside the center console), and one isn't enough.

I'm still drawing up the plans on how to wire this, but the plan is to put two in the back seat (probably mounted on the backside of the center console, below the air vents and behind where the garbage bag would be if I actually used that holder.

Also plan to add one in the trunk/cargo area, and one under the globe box for the front passenger.

None of them would ever run anything more power hungry than a 15" laptop. No fridge. No heavy duty equipment. It's primarily for laptops and charging mobile devices for passengers. However, it is conceivable that I could have several people in the car all using the power sockets at the same time.

(Notwithstanding the one in the cargo/trunk area, which would be used only occasionally and not likely when anything else in the car is in use.)


Should I be adding a second battery to the car to accommodate this scenario? I would think the current power supply while the car is running is more than sufficient since I won't be using any big equipment like a fridge, but thought I'd ask y'all what you think.


dt

Just throwing this out there for s&g. As you may know already, converting DC to AC and then back to DC for your electrical gadgets is inefficient.

My needs:
laptop - I use a DC to DC converter made by Targas
iphone, droid phone, ipad, Nexus 7 tablet - all use an USB socket
fridge - both of my fridges use 12vdc
HAM radio - 12vdc

 

[xpeppyx]

I wouldn't feel comfortable running a laptop or any more complicated electronic off of the stock inverter. I highly doubt Toyota would spec a pure sine inverter due to cost. Modified sine will cause damage over time.

 

[m85476585]

I wouldn't feel comfortable running a laptop or any more complicated electronic off of the stock inverter. I highly doubt Toyota would spec a pure sine inverter due to cost. Modified sine will cause damage over time.

Maybe. Power supplies definitely run hotter on modified sine power, and it's less efficient than pure sine, but it shouldn't cause damage. If it does, it would just be the power supply, which is often easily replaceable (though not cheap for most laptops).

 

[2014 Warthog]

For charging phones and running an air pump for a mattress for a shot time, no big deal, no need for second battery.

But laptops can be surprisingly power hungry and AC inverters introduce another 10% drain by themselves. My smallish laptop for my scope drains a decent standard size deep cycle battery in about 5-6 hours through an inverter. So you would have to possibly be careful in that case! A second battery might be just the thing. OR you can upgrade to a giant group31 marine battery which is what I did.

A super lightweight laptop or tablet would last a lot longer of course.

 

[T4RNightHawk]

I would be careful about putting ports in the back of the center console. Make sure you get shallow ports. I tried it and you have to cut into the air system and even then you only have about 1.25-1.5 inches in there. My ports didn't really fit and installation was a pain.

 

[Lewis&Clark]

Just throwing this out there for s&g. As you may know already, converting DC to AC and then back to DC for your electrical gadgets is inefficient.

My needs:
laptop - I use a DC to DC converter made by Targas
iphone, droid phone, ipad, Nexus 7 tablet - all use an USB socket
fridge - both of my fridges use 12vdc
HAM radio - 12vdc

Inefficient because inverters can use up to 20% of their power supply just for the conversion, thus reducing the total amount of power they would otherwise offer? Or are you referring to something else?

 

[Lewis&Clark]

For charging phones and running an air pump for a mattress for a shot time, no big deal, no need for second battery.

But laptops can be surprisingly power hungry and AC inverters introduce another 10% drain by themselves. My smallish laptop for my scope drains a decent standard size deep cycle battery in about 5-6 hours through an inverter. So you would have to possibly be careful in that case! A second battery might be just the thing. OR you can upgrade to a giant group31 marine battery which is what I did.

A super lightweight laptop or tablet would last a lot longer of course.

Right, but now you're talking about running it with the engine off, right? My use case is exclusively running devices while the engine is on. In such a case, the alternator will prevent any run down of the battery, right?

 

[Lewis&Clark]

I would be careful about putting ports in the back of the center console. Make sure you get shallow ports. I tried it and you have to cut into the air system and even then you only have about 1.25-1.5 inches in there. My ports didn't really fit and installation was a pain.

Hmmm. Thanks for that. As I said, I was potentially looking at that area, but I haven't taken off the paneling yet to see how much space is in there.

Another spot I was thinking was directly underneath the back seats on the driver and passenger side. Specifically, the area where the carpeting goes up towards the seat itself. Granted, I have no idea what's behind there either. But the area looks like it might have more space to work with.

 

[Lewis&Clark]

OR you can upgrade to a giant group31 marine battery which is what I did.

Were you able to make that fit in the existing battery area without significant modifications?

 

[2014 Warthog]

Right, but now you're talking about running it with the engine off, right? My use case is exclusively running devices while the engine is on. In such a case, the alternator will prevent any run down of the battery, right?

Right, no problem with engine on. In fact unless you were going to get a fridge or did want to use your laptop for say image editing at night for hours and hours, I don't see any need for a second or larger battery at all from what you've described

Were you able to make that fit in the existing battery area without significant modifications?

It does fit! You may have to bend the bus bar or lengthen it or something depending on the exact battery but it works. Just make sure if you DO get a non stock battery that the +/- are on the right sides or it definitely won't work

But as I said above, I don't see any reason to go whole hog just yet.

 

[morphious]

[MENTION=79317]Lewis&Clark[/MENTION] Maybe this will help give you some ideas:

http://www.toyota-4runner.org/4th-gen-t4rs/199237-electrical-upgrade-rebuild-complete.html

 

[Lewis&Clark]

[MENTION=79317]Lewis&Clark[/MENTION] Maybe this will help give you some ideas:

http://www.toyota-4runner.org/4th-gen-t4rs/199237-electrical-upgrade-rebuild-complete.html

Wicked cool install John. Thanks for that. Impressive setup you've got there. And impressive electrical skills--far more advanced than I, obviously! Hmmm....you're only a quick drive the I-5 from here...

I particularly liked the idea of the two LED voltage meters to keep an eye on the system when it's in use. I have the heated seats, so I'd go looking for somewhere else to mount the meters.

The other issue is where to my inverter. I'm not a fan of losing current functionality or space, and that includes giving up my glove box. Won't really fit under the seats with the power seat controls, and there isn't much of a flat area on the bottom side of the dash. Probably not going to find very many places in the cabin; I suspect I'll have to look at throwing it into the back.

I still have two unused single pole, single throw 12 volt switches mounted up front near my dash; leftover from completing the nav override mod. (Installed a few extra for future use.) Was thinking I might try to wire up all the extra power outlets to one of those two switches so I could turn the whole set of outlets on and off (assuming I don't run a second, isolated battery). Unless it were possible to wire them to the same switch that controls the OEM 115v outlet in the center console.