Notebook computers have evolved from behemoths getting ridiculously short battery life to thin, light models that can go all day away from a power outlet. All day battery life should be the target for all laptops.
Chances are you can remember laptops with giant power bricks that could only last a couple of hours unplugged. It's easy to forget that wasn't that long ago given today's skinny notebooks that can last hours on a charge. Even though things have vastly improved in regards to battery life, many OEMs are choosing to skimp in this area to keep costs down. Let's face it, a computer designed to run on batteries should be able to do so all day.
Mobile is currently the hottest gadget category, and that should include laptops. They are portable by design, and are often used away from a desktop and thus nowhere near a power outlet. Notebooks should be able to go all day on battery power, and that means at least 8 hours.
There are prospective buyers, both consumers and enterprises, who are comparing tablets with 10+ hours battery life with these notebooks that only get around five hours.
There are notebooks that can do that, but far too many cannot. Read a few reviews of name brand laptops and you'll often find the complaint that they only last four or five hours on a charge. That's too short for a brand new laptop, as after a year of typical use that battery life will get even shorter. This means these portable computers aren't very mobile by design, and that's usually to keep manufacturing costs down.
The laptop segment is being pushed hard by tablet sales, and this makes it even more important for notebook battery life to improve. There are prospective buyers, both consumers and enterprises, who are comparing tablets with 10+ hours battery life with these notebooks that only get around five hours. That doesn't compare favorably under any circumstances.
There's only one reason why laptops don't get better battery life, and that's the size of the battery used. Sure OEMs want to keep notebooks as small and light as possible, but doing so by cutting battery life short is not a good compromise.
Not everyone needs to go 8 hours on a charge every day, but it makes sense to have that option if needed. To spend time frantically looking for a power outlet to keep from shutting down is silly in this day and age. The laptop should be able to handle an entire work day when pressed.
Some companies issue laptops to workers that never leave the office, and the argument can be made that these notebooks don't need good battery life. While technically true, if organizations discourage or prohibit workers from taking the system out of the office, they shouldn't be issuing laptops in the first place. Desktop systems are cheaper and can be upgraded to extend the working life, so those make more sense in that type of environment than laptops.
Consumers or enterprises that have mobile workers, especially those travelling on business, definitely need all day battery life. That means at least 8 hours in this writer's view, and not an hour less. Like it or not, laptop makers are going up against long-running tablets, and they'd better compare more favorably than they are now.