Battery power can be maximized by following these simple suggestions.

• Use BlackBerry smartphone shortcuts to access common system features quickly. For instructions, see KB02867 and the Getting Started Guide for your BlackBerry smartphone. Using shortcuts allows you to do the same things on your BlackBerry smartphone more quickly and efficiently, while saving battery power.
  

Some common shortcuts include the following:

• To delete a highlighted item, press the Delete key.
• To select or clear a check box, press the Space key.
• To view available values in a field, press the Alt key.
• To switch applications:
• 1. Hold the Alt key and press the Escape key.
  2. Continue to hold the Alt key and highlight an application.
  3. Release the Alt key.

• Set the Auto On/Off option to turn off the BlackBerry smartphone at a time of day when you are not using it (such as at night), and turn on again at a time of day that you are ready to use it (such as in the morning just before you wake up). Battery power is saved by turning the power off at times when the BlackBerry smartphone is not being used.

To set the Auto On/Off option on the BlackBerry smartphone, complete the following steps:

1. On the Home screen, open Options.
2. Select Auto On/Off.
3. Specify the on and off times.

Tip: Set the BlackBerry smartphone to turn on just before you need to use it, (such as a few minutes before you wake up in the morning) so that the BlackBerry smartphone has a chance to receive the email messages sent to you during the time that the BlackBerry smartphone was turned off. This way, the email messages have already been received when you are ready to read them.

• When a particular wireless connection is not needed, use the Manage Connections application on the BlackBerry smartphone to turn off the connection. For example, if you do not need to use Bluetooth® technology, you can use Manage Connections to turn the Bluetooth connection off.
  

To turn the Bluetooth connection off on the BlackBerry smartphone, complete the following steps:

1. On the Home screen, open Manage Connections.
2. Click Bluetooth.

Note: Using Manage Connections, turn the mobile wireless transceiver off when you know you are out of range of the mobile network. Turning the mobile wireless transceiver off prevents the BlackBerry smartphone from continually attempting to locate the mobile network, which uses a lot of battery power.

another suggestion is to use google mail application. and create a filter in your webclient just to push level 1 message and work related email.

and don't let the google app running on background. hence you have combination of push and pull email solutions.