Questions regarding M4700 battery life

Hello

I just picked up a Dell factory certified refurbished M4700 from Ebay, just waiting for it in the mail.

I had some questions regarding the battery life of the m4700. Coming from a Thinkpad T530, I know the Dell will not do as well, but I am looking for some real world battery life figures.

My spec (relevant to battery life)
- 1080p Screen
- Intel I7 3740qm
- 256gb SSD
- K2000m graphics
- 9 cell (87wh) 3 year warranty battery

Questions:
1. So how many hours would I be getting realistically, doing basic word document work and wifi internet?
2. I have always taken my battery out once it charged fully on my previous laptops, is this necessary with my Dell? or Can I disable charging in the settings?
3. How much real life difference is there between 97Wh 9 cell and 87Wh 9 cell?
4. I also have a 97Wh battery slice coming in the mail as well, how long would the battery last combining 87Wh internal battery and the 97Wh battery slice?

Thanks!

 

I get any where from 2 - 3 hours depending on screen brightness, and if I use wifi etc.

 

Wow that is way too short for me.

I am now considering switching to Latitude E6530. I chose the precision m4700 over latitude e6530 because of $200 price difference, but much better specs with the ssd and the quadro graphics card, not to mention the better build quality for the precision. But if precision m4700 has that bad of a battery life, this is not good.

Does the latitude E6530 have much longer battery life, even with a same battery, compared to a precision?

How about the testing from PCMag? http://www.pcmag.com/image_popup/0,1740,iid=365102,00.asp

 

On my M6700 (97Wh) I get in that range when doing basic work (with no effort to think about shutting off background apps, lowering brightness, etc.). This is with Optimus off, you can probably add another 1-1.5 hours with Optimus enabled at a minimum.

It's possible to get much better if you are willing to do some work to reduce your power usage. An example is Bokeh's 11-hour runtime on the M6600 from his M6600 review.