I'm planning to purchase a used T480, and want to know how the battery life would be on Linux. Online I see a lot of good numbers, and I am considering carrying multiple of the external batteries, but I want another opinion. Also, do you have any recommends on a good price to "go for it" and any other laptops to consider (up to but preferably well under 600 USD, good battery/portability, linux) to consider.
I'd say no more than 200$ for the T480. Since you mentioned portability, it's not very portable compared to the S models of the T series and even less to the X series.
One advantage of the t480 is having two memory slots for easy and cheap ram upgrades, with all others you have to make sure they have at least 16gb (or 8gb soldered on one side)
The portability carries a big bump in price, if you see a cheap T480S, X1 carbon 6th, X390, you might be happier with those.
We also have to consider that from 300$ upwards we are talking Ryzen Zen 2 (used) prices, maybe from the L series but you might catch the occasional T14 AMD for 400$ which is a considerable upgrade in every metric.
I heard the T480 had a swappable battery, which might be nice. Weight is less of a concern than battery life. Would this change your assessment? Thanks.
Long story short: nowadays 65W-capable USB C powerbanks make more sense in my opinion, than multiple Thinkpad batteries. And they work with all laptops.
Yep just like the S versions they have a double battery. This is great because the total can get close to 100Wh (when using the 72Wh external) but hot-swapping requires an internal battery in good shape which is not so easy to come by. From Lenovo they can be very expensive or not available. From third parties you're always gambling that those batteries will play nice with the proprietary Thinkpad EC.
I bought both (3rd-party) batteries for a T440S, and the internal would suddenly show up as 0% every couple of weeks, and had to be "reset" by opening the base, unplugging and plugging it in..in the end I just put the original internal back; the external has been amazing instead, and it does basically all of the work since it's the 72Wh version. Fun fact: these laptops work perfectly with only one of the batteries attached.
All thinkpads (at least all T series) have easily swappable batteries. The T480 has 2 batteries, one external and one internal. Older models had only external, newer models have only internal. The only advantage of the T480s battery setup is that you can get 100 watt hours in the laptop. The gen that came out right after it only has like 50 or 60, but I think the T14 gen 3 and newer machines have bigger batteries.