External Battery Pack Option

[cedric5555]

1) If an external battery/power is attached, it will run the Surface AND charge the Surface from the external battery at the same time. The internal Surface battery will head toward 100% as the external power is consumed. The only exception would be if the external battery was not able to keep up with the >3 amp that the Surface pulls while operating and charging. But you do not want an external power device that can't keep up. You get into a lot of issues. The Intocircuit 26000 will keep up with it.

2) Sorry but your math is off. The Intocircuit is a single huge 26000maHr cell. About 4 volts. The Surface is TWO cells at what(?) 5600maHr.
So the Intocircuit is about 104 watt hours. the Surface is maybe about 44.8 watt hours (?). Don't forget to add in the power supply inefficiencies, and you are looking at maybe 2 full recharges.
The XP18000 is smaller so also surely a single cell. At 4 volts, that is 72 watt hours. Or about 1.5 charges.

(I don't have the actual Surface battery numbers in front of me. Those are a guess. And 3.8 volt cell voltages are probably more reasonable for the math, but the results are the same.)

A car battery is generally well over 300 watt hours BTW, if you can get to a car.

Then there is the bigger issue. 12.5 hours of gaming while camping! mg:

Wayne,
Thanks for your info. Now it makes more sense.
iFixit teardown shows Surface Pro is a tough nut to crack | Ars Technica
I got the battery info from the above link.
Surface Pro Battery: is an LG-produced "Escalade" lithium-ion unit rated for 7.4V and 5676mAh.
So it is 42 watt hours.

Introcircuit: 26000mah with about 4v (I can't find the info from web. Where did you get it?)
so it is 104 watt hours.

Therefore, the Introcircuit can have a little more than 2 fully charges on Pro.

That will be 2 + 4 = 6 gaming hours or 4 + 8 = 12 hours for normal use which is pretty good.

PS: 12.5 non stop gaming hours just an example. Let's say its 3 days two nights trip. Each day is about 4 hours operation time that isn't too bad. (movies or play songs on the car or during the day, gaming at night with friends)


Few more questions
1) May I ask if I can charge the Intocircuit (charging from wall socket)and charge the Pro at the same time? Will it get overheat? (In this case, I don't need to carry the Pro AC adapter)

2)The Intocircuit has a switch for three options DC*12V/ 16V/ 19V. Which one should I use for the Pro?

Thaks for your info and advice. ^_^

 

[Cambo]

I have had no heatng issues while charging the introcircuit and having it plugged to the surface..make sure you don not change the voltage on it...keep it at twelve volts

 

[Russ]

Russ, According to your test, you said you started in the early evening which is around 6pm or 7pm. When you woke up the next morning, the pro is still running.

Alan --

No, that is not what I said. What I said was "the next morning, the Pro had gone to sleep due to inactivity, meaning that it switched to its own battery when the external was completely discharged." That was the purpose of my test. I wanted to know if the Pro would interpret a fully discharged external battery as being "not plugged" in, and then revert to the power settings for its own battery power. It did.

Sorry for any confusion.

Regards,
Russ

p.s.: Pay attention to Wayne. He know more about this stuff than any of us.

 

[Wayne Orwig]

Wayne,
Thanks for your info. Now it makes more sense.
iFixit teardown shows Surface Pro is a tough nut to crack | Ars Technica
I got the battery info from the above link.
Surface Pro Battery: is an LG-produced "Escalade" lithium-ion unit rated for 7.4V and 5676mAh.
So it is 42 watt hours.

Introcircuit: 26000mah with about 4v (I can't find the info from web. Where did you get it?)
so it is 104 watt hours.

Therefore, the Introcircuit can have a little more than 2 fully charges on Pro.

That will be 2 + 4 = 6 gaming hours or 4 + 8 = 12 hours for normal use which is pretty good.

PS: 12.5 non stop gaming hours just an example. Let's say its 3 days two nights trip. Each day is about 4 hours operation time that isn't too bad. (movies or play songs on the car or during the day, gaming at night with friends)


Few more questions
1) May I ask if I can charge the Intocircuit (charging from wall socket)and charge the Pro at the same time? Will it get overheat? (In this case, I don't need to carry the Pro AC adapter)

2)The Intocircuit has a switch for three options DC*12V/ 16V/ 19V. Which one should I use for the Pro?

Thaks for your info and advice. ^_^

The voltage is standard lithium ion. They are is low as 3.2 volts and as high as 4.2.
If the Surface Pro is 7.4, then they are calling each cell 3.7 volts. So to be equivalent, you might want to call the Intocircuit a 3.7 volt single cell for the conversion.
The Surface Pro is 12 volts ONLY. I put a bit of glue on the switch to reduce the risk of damaging the Pro.

You can charge the Intocircuit at the same time that it charges the Pro (and a cell phone in fact). But, the charger for the Intocircuit is 37 watts, so if everything is low, it will take a LONG time. And if you run the Pro at the same time (10 to 20 watts), it may be a REALLY slow charge.

 

[dyelongjustice]

Not sure if this has been posted yet, but I found an extremely easy workaround for an external battery pack option, and one that is cheaper than MikeGyver.

This battery from Amazon: Amazon.com: Anker Astro Pro2 20000mAh Ultra-High Capacity Multi-Voltage External Battery Charger Power Pack for Tablets, Netbooks, Notebooks, Laptops and Smart Phones - Compatible with HP, Dell, Acer, Asus, Toshiba Notebooks, Google Nexus Tablets, iP

And this connector from eBay: Wall Charger Cable for Microsoft Surface RT Surface Pro | eBay

Works like a charm, and no modifying necessary. Plus, the battery looks a lot like the one MikeGyver uses...

 

[gangolfus]

Good to know that combo works. I just bought that battery pack for a 12v outdoor LED lighting project and having it double as a battery booster for my Surface Pro would be an added bonus. If only I could find a compatible magsafe2 connector for the lady's MacBook Air, it would be perfect.

 

[dyelongjustice]

I just did a very quick and unscientific test to see how much charge this battery could give (I'm not sure of the math to convert the mAh to W). I let my surface pro run down almost completely (15% left). I then put it to sleep, and used the fully charged anker external battery I bought to charge the surface. It took 2 hours to completely recharge the surface, and the external battery is showing 1 light left (meaning it has 20% or less left). So basically, your going to get almost 1 full charge out of this external battery using the parts I have bought...

 

[Russ]

the battery looks a lot like the one MikeGyver uses...

Mike is using the Intocircuit 26000mAh battery. It is also available on Amazon.

A couple of people here have also used the Anker battery.

Regards,
Russ

 

[Padron26]

Can you guys tell me if mikes charging cable have the light indicator working.

 

[Wayne Orwig]

Can you guys tell me if mikes charging cable have the light indicator working.

No light.
I've had a few times where the plug pulls out of the battery pack slightly, and it doesn't charge. And it isn't obvious that it has stopped charging. I now occasionally pull up the battery status to be sure it is on charge.

 

[heed]

I just did a very quick and unscientific test to see how much charge this battery could give (I'm not sure of the math to convert the mAh to W). I let my surface pro run down almost completely (15% left). I then put it to sleep, and used the fully charged anker external battery I bought to charge the surface. It took 2 hours to completely recharge the surface, and the external battery is showing 1 light left (meaning it has 20% or less left). So basically, your going to get almost 1 full charge out of this external battery using the parts I have bought...

This is using the parts you referenced in the above post? I think I will pull the trigger on the same parts if so...

 

[Padron26]

Wayne are you using a oem MS plug or a (eBay) Chinese mag connector.

I notice that the cheaper version mag connectors seem cheaper..obviously. I also notice with the cheaper connectors that it will spark if I don't align the connector just rite on the surface. Which happens about everytime.