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I'd like to find out more about charging small accessories like USB-C macbook or magsafe 2 macbook pro off the 12 volt system. The EVExtend 1500W inverter seems overkill for this, although I will eventually get one of these for Volt camp-mode!

Perhaps there's sufficient ways to adapt the macbook pro chargers to the 12 volt system? Ideally, this is as power efficient as possible.
I'm thinking something like this for MagSafe 2
https://www.amazon.com/WeCharger-Ultra-Compact-Portable-MacBook-Connector/dp/B00ETCD9BC/ref=pd_sim_147_1?_encoding=UTF8&pd_rd_i=B00ETCD9BC&pd_rd_r=BESHYA0709S6JA7BBVHP&pd_rd_w=WRNcL&pd_rd_wg=n4QvN&psc=1&refRID=BESHYA0709S6JA7BBVHP#Ask
 

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I'd like to find out more about charging small accessories like USB-C macbook or magsafe 2 macbook pro off the 12 volt system. The EVExtend 1500W inverter seems overkill for this, although I will eventually get one of these for Volt camp-mode!

Perhaps there's sufficient ways to adapt the macbook pro chargers to the 12 volt system? Ideally, this is as power efficient as possible.
I'm thinking something like this for MagSafe 2
https://www.amazon.com/WeCharger-Ultra-Compact-Portable-MacBook-Connector/dp/B00ETCD9BC/ref=pd_sim_147_1?_encoding=UTF8&pd_rd_i=B00ETCD9BC&pd_rd_r=BESHYA0709S6JA7BBVHP&pd_rd_w=WRNcL&pd_rd_wg=n4QvN&psc=1&refRID=BESHYA0709S6JA7BBVHP#Ask



Seems legit!:rolleyes:
 

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NO, absolutely not. The MacBook Pro with MagSafe needs 16v DC which you cannot get from the 12v car power plug. You can, however, get an inverter, then convert that 110v back to the macbook's magsafe using the Apple-supplied power supply.

As for USB type C, the MacBook comes with a 29W adapter. My MacBook Pro with USB type-c and touchbar comes with an 87W power adapter. No cigarette style power adapter can supply its USB port with this much power directly to a USB cable. Adapting a type A to a Type-c will be problematic. Don't risk frying your expensive MacBook. The most power I've seen in a type A power plug is 12W. Not enough for any MacBook.

I would not trust any of these unsafe adapters coming out of China and other places.
 

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Careful with the inverters though. I had a small inverter (12v plug to two 120v outlets) which was rated for 75w that I used to use with an older car. Whenever I left it plugged in after driving, I found it would backfeed electricity into the car after I shut the car off. Never damaged anything but caused all kinds of weirdness with the electronics (e.g. radio powering up with car off, etc...)
 

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NO, absolutely not. The MacBook Pro with MagSafe needs 16v DC which you cannot get from the 12v car power plug. You can, however, get an inverter, then convert that 110v back to the macbook's magsafe using the Apple-supplied power supply.
A DC-DC converter can produce 16V from a 12V source. I've got a Dewalt battery charger that charges 18V packs from 12V.

Apple used to sell a Magsafe Airline adapter. The airline standard is EmPower which is a 15V system limited to 75 watts. Automotive "12V" systems are actually closer to 14V so 15V isn't that much different. The trick with the Airline adapters is that they don't allow charging of the laptop's battery for safety reasons.
 

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A DC-DC converter can produce 16V from a 12V source. I've got a Dewalt battery charger that charges 18V packs from 12V.

Apple used to sell a Magsafe Airline adapter. The airline standard is EmPower which is a 15V system limited to 75 watts. Automotive "12V" systems are actually closer to 14V so 15V isn't that much different. The trick with the Airline adapters is that they don't allow charging of the laptop's battery for safety reasons.
Agreed, technically you can use a transformer to get the voltage you need, but experience shows that unless Apple makes it, you get this (the charred pic in post #2)

http://gm-volt.com/forum/showthread.php?278929-Charge-small-electronics&p=3908249#post3908249

There are tons of cheap power adapters on Amazon that are Chinese clones as well as substandard power cables. Even Apple implemented a USB type-c cable replacement program when the first MacBook appeared in April 2016 because of safety concerns. They automatically sent me two replacement cables (I had two wires, one for work, one for home. Interestingly enough, now that I'm carrying a 15" MacBook Pro with a touchbar, those wires are noticeably thicker than the USB type-c wire that came with my MacBook. It makes me wonder if it is safe to use the thinner MacBook type-c cable with my MacBook Pro and the 87W adapter. I'm not gonna try it for fear of frying something. I have, plugged the 29W adapter into the MacBook Pro, and it, as expected, barely keeps up with the power usage.
 

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Discussion Starter #12


Seems legit!:rolleyes:
Very legit! I was curious if the inverters created additional load on the car, since they are only 80-90% efficient to begin with. I couldn't find any legit DC-DC magsafe 2 adapters. I think for IP reasons, nobody can make magsafe 2 plugs. So it looks like Inverter is the only possible solution.

From my testing, the new MBP USB-C will charge from the iPad Pro 27watt charger. Verizon does make one (out of stock) https://www.verizonwireless.com/accessories/verizon-usb-type-c-car-charger-with-fast-charge-technology-typecpdvpc/ and Belkin will have one eventually http://www.belkin.com/us/p/P-F7U004/.
 

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Discussion Starter #13
You can get small inverters in the 150 watt range that have a short cable and cigarette lighter plug that are convenient to use in the console area and will charge a variety of small electronics through the 120 volt outlet.

The one I use is sold here:
https://www.amazon.com/gp/product/B01DR2RLDQ/ref=oh_aui_detailpage_o06_s00?ie=UTF8&psc=1
What laptop do you charge with it? Do you have issues with overheating? The Kensington one on Apple's store page has conflicting information about charging the 15'' MBP. Some say it work, some say it doesn't but they all agree the fan on it is loud and annoying. Would it be worth getting a larger pure sine wave inverter to avoid these issues?
 

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Discussion Starter #14
As an update, I bought the Bestek 400watt. https://www.amazon.com/BESTEK-Power-Inverter-Adapter-Charging/dp/B00UFERZKO/ It recommends not pulling more than 150watt from a cigarette lighter. Anybody know what the wattage max is on the 3 cigarette lighters in a 2014 Volt? Maybe point me in the direction to find that information?

I am a little concerned on the size, so will update here after setting it up. The 300watt is more compact and might be a better fit for this vehicle and I might regret having gone too big!
400watt dimension 11.7 x 6.9 x 3.1 inches
300watt dimension 4.8 x 3.1 x 1.9 inches
 

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Discussion Starter #15
I have my inverter in hand. I've read that the 20amp fuses on the cigarette lighters are only good to 240watts. This 400 watt inverters could blow those. I ordered a EVExtend kit, so I can tap into the APM board.

I hooked the inverter up to the trunk battery and power works great even without the car being on. The location isn't ideal since lowering the carpet knocks into the battery clips. Since the car is off, I can run this battery down by using the inverter. What will happen if I do this? Will my car still start with a dead back battery? If I turn on the car when pulling from the trunk battery, will it maintain this back battery?
 

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I have my inverter in hand. I've read that the 20amp fuses on the cigarette lighters are only good to 240watts. This 400 watt inverters could blow those. I ordered a EVExtend kit, so I can tap into the APM board.

I hooked the inverter up to the trunk battery and power works great even without the car being on. The location isn't ideal since lowering the carpet knocks into the battery clips. Since the car is off, I can run this battery down by using the inverter. What will happen if I do this? Will my car still start with a dead back battery? If I turn on the car when pulling from the trunk battery, will it maintain this back battery?
If the 12V battery is dead then your car is dead. The car can't "turn on" the high voltage battery without 12V power to run the control systems.

What's worse, if the 12V battery is low, it can cause bad sensor readings which can also disable the car and require a trip to the service department to reset. I strongly recommend being very careful not to drain the 12V battery.

When the car is turned on ("Ready" indication visible on the dash) the high voltage battery is connected and it will charge the 12V battery. If that drains the high voltage battery then the engine will come on to recharge it, as long as the car is not in neutral.
 

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Discussion Starter #17
Installed my 400watt inverter the proper way, thanks evextend! Still a little wary about the 12volt system and how much bare metal is showing on this inverter hookup kit. With the right motions, the two cables can likely touch. So I'll be wrapping those with electrical tape to prevent it.

In this picture, I'm powering via my Volt the lamp I used to install the kit itself. Super simple install, took me roughly an hour from start to finish. I recommend the Husky hollow ratchets so you don't need to buy specialty deep sockets.
 

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Read through this and do not totally understand the warning about max allowed voltage specs in regards to charging a MBP through the cigarette lighter, is there in fact any consensus on the safest way/safest cord to use for charging a new MBP? Or is it best to avoid even trying?

Love the idea of taking my car to the park/beach, not burn any gas, and be able to sit with the A/C on & get work done without worrying about the laptop battery.
 
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