What can I do to improve my laptop battery life?

         If your laptop is shutting down abruptly, it means your laptop needs to be Recalibrated  . Recalibration doesn't improve  laptop battery life - Windows is simply better informed on how long it should expect your battery to last. Here are instructions:How to Calibrate Your Laptop Battery For Accurate Battery Life Estimates. 

        Li-ion batteries lose approx 20% of capacity per year at room temperature.If  your laptop is over 5 years old, the capacity loss you are experiencing is normal. If you continue to run the battery through several deep discharge cycles, it's capacity will drop even further. 

          There are a couple of troubleshooting steps you can try, but these are for when capacity is lower than expected. This is not the case for you, so I suspect they will do you no good.

 1.Force-reset Microsoft battery drivers - to do this, remove your  laptop battery, power up your laptop, go into device manager and uninstall all drivers listed under 'Battery'. Then shut down the machine, re-install the battery and power it up again.

2.Upgrade your BIOS - You should be on version 3.10.

3.Check for laptop heat issues - Battery capacity can be severely impaired if a nearby component is overheating due to blocked vents or dusty fans.

4.Cool the battery down (caution advised!) - Wrap the battery up tightly in paper towels or newspapers, seal it in an airtight ziploc bag squeezing out as much air as possible, and place it in your refrigerator (not freezer) for at least a day. Remove the bag and let it return to room temperature before removing the laptop battery and testing it. Don't remove the battery from the bag while still cool to avoid condensation.

5.After all this is done,the battery is still the same as before ,so you have to consider buying a new battery as a replacement battery.
  Aftermarket batteries for your laptop are available ,  so that's really the way to replace. However, your options may well be limited if you don't consider the aftermarket batteries.

Another option if you are comfortable using a soldering iron (again, caution strongly advised) is to rebuild your battery with individual Li-ion cells, either bought new  or reclaimed from other laptop batteries. Instructions here: How to rebuild a Li-ion battery pack. When working with Li-ion batteries, keep away from inflammable objects, wear eye and skin protection, and keep a bucket of sand handy.

Also take a look at the service configuration guide for your version of Windows, so you can disable unnecessary services such as search indexing: Service Configurations.

Hopefully this will help you improve your laptop battery.