Surface pro Power bank

SyStemDeMoN

My son has just had a Tobii eye gaze as a communication aid and it uses a MS surface pro to run the software.  Basically my son can control the Surface with nothing more than his eyes.
Its a great bit of kit but the battery life on the Surface is pretty poor compared to his previous aid.
Is there a good power bank I can use to give it a bit more life when out and about ?

SyStemDeMoN

My sons college have proposed a fix.  They are going to somehow wire a charging lead from the wheelchair batteries as this Surface has about 4 hours battery life.

depot

Thats a good idea, i've been looking for a power bank for the surface pro, the only reasonable one the Qi-inifinty which seems to be usa only.

dannnielll

What. Power does  the surface draw.  E.g what is its Voltage and current.. it would be on the manual or even on the power supply adapter.

Bubblin

Is it a 2017 surface pro, if so I’m afraid his runs via a proprietary power cord at 65w, so the power bank won’t work as you’d expect, older models I think charge via usb and will be able to use the power bank, but at an average of 10w won’t charge or sustain the power quite as expected.

dannnielll

I asked previously what power was the surface computer drawing, as that determines the way to  go. Some of the older models work at 30watts but it looks that there are models at 65 watts.  The simplest kludge fix is to get a set of 3  li ion cells wired in series and fed into a cheap halfords or Maplin  12v to 220v invertor . Then use the cable adaptor which came with the  Surface to power it. Those cells are good for say 2 hours at 30 watts . If you need more then they can be paralleled. A cheaper alternative is to use a mobility battery at 12v at say 10amphr  and it will work for say 3 hrs. .. if the actual power consumed is less the battery duration is pro rata.
A number of the mobility scooter s use a 24 v supply, and the invertors  used by the big freight lorry drivers also use 24v, so just piggyback one of these to the electrics would be even simpler

SyStemDeMoN

I'm not sure about the power requirements.

Just to clarify it is this :
EyeMobile Plus Access – Featuring Windows Control & Surface With Microsoft - Tobii Dynavox

I have left it at my sons college over the holidays so the IT department can get in touch with a company that has said they may be able to provide a hard wired solution from my sons wheelchair batteries.
His wheelchair can hold a charge for a few days.  As long as it last a day that would be fine as we can charge the wheelchair overnight.  The wheel chair does have 2 car batteries so I'm not sure if its 12v or chained 24v.

dannnielll

Thank youy for the detail, I now  know what you and your son are up against.I  would suspect the that the vechicle power is a total of 24 volts, at least it was with my mother's wheelchair. . That being the case the inelegant solution of just using a 24 volts invertor and then the ordinary power adaptors. Is proablpr the best solution..