Possible GPU upgrade for Precision M4600

Not true.
They can try for sure.
Take a look at this 27,000mAh portable laptop charger which has more than 4 times the capacity of M4600 batteries:
This one's TSA (airline security checkup) approved:
https://www.ebay.com/itm/ChargeTech...373555&hash=item465bc85d58:g:gDgAAOSw9GhYbZbb

You can take it on airplane because they have TSA approved mark.
So if a third party company makes something like this for Dell M4600, they can do a good business.

Here's another attempt:
https://www.amazon.com/Portable-Gen...pID=41F1oFKaCuL&preST=_SY300_QL70_&dpSrc=srch

 

M4600 can already use an extended battery from Dell
https://www.amazon.com/312-1351-9CE...625107&sr=8-2-fkmr0&keywords=dell+kj123+slice

This one gives you additional 8,000mAh. You can install this at bottom of your M4600 and get 16,000mAh total combine with your original battery.
However, this product is still from 2011.

In 2011, they had to use that huge enclosure for batteries.
In 2018, they no longer need to.. or they can do perhaps 38,000mAh for the same size.
Battery's capacity ( mAh) has nothing to do with Whr.
You can increase capacity and get more hours... and I think this is 100% possible.

That's why so many companies make extended cellphone batteries:
https://www.amazon.com/Battery-Maxb...8625275&sr=1-3&keywords=extended+battery+case

 

It's worth keeping in mind that batteries do age and lose capacity in time. Even if your stock battery says 8000mAh on it, you can be quite sure it won't provide that much today. My 9-cell, for example, is rated for 99Wh, but can only hold 82Wh nowadays, about 4 years lated (although granted, i haven't used / abused it much).

You might be forgetting about good old Ohm's law (and its derivatives), though.

The batteries in our laptops are usually strings of 3 cells in series. However many cells you series up, the mAh figure stays the same as for a single cell. For example, a 6-cell pack will have a string of 3 sets of 2 cells in parallel; a 9-cell pack will have a 3S3P configuration.

Watt-hours is the above-mentioned mAh multiplied by (usually) the nominal voltage of the pack configuration, ie. 3.7v for a single cell (or multiple in parallel), 7.4v for two in series, 11.1v for three in series, etc.

So i'm really sorry, but Wh are directly and inextricably related to mAh

 

Yeah, 8,000mAh for M4600 isn't big enough anymore.
Even smartphones come with 5,000mAh now:
https://www.ebay.com/itm/BLU-Life-O...136370&hash=item33e13597fb:g:6ooAAOSww-BadNY4

I hope a third party company makes 20,000mAh TSA approved M4600 batteries... and it's going to be possible to do.
No one seems to be doing this yet.. although there are lots of third parties making the same spec M4600 batteries (5600mAh - 8000mAh)
That's spec of 2011... and I don't think that's valid anymore.
GPU and CPU on M4600 are still valid. Dell FHD display is still better than Lenovo display.
Dell hardware design on M4600 is still better than Lenovo's.

 

At that point you'll be past the weight of the m6600 for a marginal increase in operation time.

Thats a pass from me

 

Smartphones may well have 5Ah batteries, but those are single-cell

I've got a phone battery in hand (out of a Marshall London phone); the ratings on it read 2500mAh 3.8v 9.50Wh. If you divide the 9.5Wh by the 3.8v nominal voltage, surprise-surprise, you'll get exactly 2.5Ah.

As mentioned earlier, in laptops you'll most often find 3-series cell configurations. Thing is, at least if counted / measured correctly, you'll still only get the mAh of a single cell.

2Ah is a pretty bog-standard capacity for an 18650 lithium-ion cell, the most widespread kind. A single cell on its own, if we count 3.7V as nominal, works out to 7.4Wh - you with me so far? If we put two in series, it's still a 2Ah battery, but the voltage is now 7.4V, and thus the energy available is 14.8Wh. Three in series and we end up with 21.6Wh.

If we have two parallel strings of 3-series cells, now we have 4Ah, as well as doubling the energy capacity from above, ie. 43.2Wh.

So you see, the plane-transportable rule is about watt-hours, NOT (milli)amp-hours.

<later edit>

A 20Ah battery, assuming only cells in parallel (ie. 3.7v nominal) would add up to 74Wh. A more realistic 3-series arrangement (ie. 10.8v nominal) with however-many cells are needed for said 20Ah figure, would end up being 216Wh.

 

Marshall London phone was a great project... with a DAC inside for HD music playing.
But Marshall was terrible at marketing and distribution so it ended up no where.
Marshall is still android 5.0 so I'm expecting to see it for under $100 soon on Ebay.

iPhone 4 which was $500 in 2010 is now only $25 on Ebay. iPhone 4 still works great just like M4600. It has durable protective metals and it still does what it will exactly said it will do.
I think iPhone 4 was Steve Job's best smartphone.

Regarding batteries, what I was saying is you can create the same battery for less than half the size (dimension) that was available in 2011.
For instance, you can use this extended battery on your M4600 to get extra 10 hours.
https://www.amazon.com/312-1351-9CE...625107&sr=8-2-fkmr0&keywords=dell+kj123+slice

What I'm saying is .. now you can make the same battery with less than half of its size.
So perhaps you can get twice of its capacity for the same size and get extra 20 hours.

I haven't studied mechanical & chemical engineering so I haven't tried this myself yet.
If there's business market for this kind of jaw-dropping extended batteries, I would like to try out personally.

 

The size thing is arguable - to really get the volume down (or to make the most of the physical space you have available), you'd need to go with custom-size LiPo cells, which won't be cheap. By comparison, the 18650's are quite the bargain, with the disadvantage that their physical packages aren't the most efficient in terms of space usage.

That being said, the volumetric capacity of lithium batteries hasn't evolved quite THAT much, actually. Sure, they can probably pack them a liiiittle bit tighter nowadays, but not without trade-offs (max charge / discharge current, self-heating etc). Or in some cases, that can even be taken too far - see the Note 7 fiasco.

 

It's been 7 years and many techniques became available.
Take a look at this for example:
https://www.amazon.com/Ultra-Slim-U...pID=31klxhjGcWL&preST=_SX300_QL70_&dpSrc=srch

This was not available in 2011. No one was manufacturing a credit card sized lithium battery but people can do that.

 

https://www.amazon.com/dp/B072JWN6L...om&pd_rd_r=QFDQ5Z9CQZRKZZTJC2SV&pd_rd_w=kP4EM

This Omni charge can power up Alienware by the way.

https://www.amazon.com/gp/customer-...ef=cm_cr_dp_d_rvw_ttl?ie=UTF8&ASIN=B072JWN6LC

It has 20,000 mAh and its volume is about the same as Dell M4600 extended slice battery (2011).