How to increase Mac battery life after upgrading to Lion or Mountain Lion
Lion on old macbook pro gives 6:26 hours at 80% battery
MAC OS X last two versions, 10.7 Lion and 10.8 Mountain Lion, decrease battery life for older mac laptops but work with minor issues on newer hardware. The problem, after testing it myself several times, is that older laptops were made for older OS versions. As obvious as that. Read the descriptions, 2007 macbook came with 1GB standard and with Core 2Duo as compared to new 4GB Intel Core I5 standard. Newer hardware works just great on newer software.
We are now going to a mobile oriented consumer market, the reports say that laptops, tablets, and mobile phone are selling much more than desktop computers. Then, more upgrades and improvements are coming for the to-go technology. That includes the 10 hours that Apple products and other tablet companies are producing for their batteries. One day laptops will come with a convenient 10+ hours battery life just like they did have an increase from a normal 5 hours battery PowerBook to a 7 hours MacBook Pro in 2009.
Almost 10 hours in new OS X update
Understanding the problem
Mac OS X lion and mountain lion are using more battery to empower the constant online connection. AirDrop, notification center, iCloud, and so all the other features that require a constant online connection are using more battery power.
Turn those features off, if not needed. Open finder and right click on the air drop and select the "remove form side bar" option. Then, Install all updates since the Apple often releases more updates to fix OS issues. Use iCloud or google drive manually instead of automatically, and close them when not in use. This will decrease RAM usage and decrease the constant connection to the online world, giving more power juice on you battery.
OS X Lion and Mountain Lion use more ram than snow leopard (which is why the minimun requirement is 2GB of ram) so have the less amount of open programs possible.
Apple will be creating solutions to further problems and send them through system updates, here is Mac os X Lion 10.7.4 (first screenshot) and Mac os X Lion 10.7.5 (second screenshot). At 85% my Macbook Pro 13" is having almost 10 hours of battery life.