What y series laptop do you have? Is it good enough for media consumption and some light 42mp photo editing?
Something that's very niche and comes with a premium price point as it's a full on 2in1
UMPC. For editing pictures think that you will need more than a Y series can offer. Intel U series will be a far better option, in which case I'd be looking at one of the new 10th Gen CPU's.
The i7-8500Y will do what you want, however it's going to hit it's PL1 (7W) limit editing large images and subsequently be limited to around 2.3GHz across just two cores (4 with hyperthreading). A lot's going to depend on your priorities runtime off mains or performance.
A lot can be done to extend the battery runtime of a W10 Ultrabook by undervolting the CPU and cutting unnecessary background applications. New Samsung Galaxy Book S might be worth investigating as it has the new ARM 8CX SOC and might just pull off both performance and battery longevity.
I've not yet tried the new ARM powered Samsung, I have tried the equally very new Huawei MateBook E with Arm Snapdragon 850, in stock configuration it was fine on a quick look. That said I'd want load it up and see what how it really performs under load. The Samsung has the 8CX so it's a level up again on the Huawei, however more a traditional clamshell notebook, versus the MateBook being a tablet centric 2in1.
MS Surface Pro & Laptop get decent runtime with regular U series i5/i7 CPU's, not sure if a 2in1 interests? I've also an Acer Switch 5 (i3, 4Gb, 128 SSD) and it's rated for 10+ hours, in the real world it more like 7 hours.
Personally I miss the Apple of yore; Always under promised, always over delivered. Once did a job, I'd have been done had the notebook shutdown midstream
2014 13" MBP pulled over two hours past it's recommended runtime
Outstanding, such a pity Apple now values itself so much more than it's customers
Q-6