Nikon: Battery Recharging?

So I have an issue - i've heard this before but I want to know if something has changed or if this is a myth?
I constantly find myself with half a battery after a regular photoshoot, I use my battery pack on my D300s. When I want to go to my next shoot, I'm paranoid cause I don't know if I can recharge it to full again or if I need to wait till it's dead. Obviously, I do not want to go into a shoot with half life.

I know my other option is to go buy 2 more battieries for it, so I always have a set charged…

I always go and find something to make the batteries die, but it's kinda of tiresome. Thoughts on this?
WOULD Really LIKE TO KNOW IF IT DOES HURT THE BATTERIES?

Batteries do deteriorate over time. I have a spare battery that I use when my primary runs out, then I charge that while my secondary runs my camera.

It is much like a laptop battery, if you charge it from half way, you are killing your battery faster and faster. If you condition the battery, meaning you only charge it when it is empty, the life of the battery will increase.

Just but a new battery.

Okay here is some of what I have learned using D100, D200, D300 and D3 Nikon's

One is that when using the battery grip on the D300, you have to tell the camera which battery to use first in the camera or in the MB-D10 grip. The remaining charge shown in your viewfinder and top LCD refers ONLY to the battery in operation.

There are ways to conserve battery power.

* turn off the camera after each shot sequence.
* if you are using the live view, expect to get only about 30% of the life from a full battery.

I usually get a full football game from one fully charged battery with plenty left over.

I switch batteries when the battery shows it is less than 10% using Battery Info in the Setup Menu

I NEVER let a fully discharged battery sit for over 12 hours. It goes on the charger as soon as I return from a shoot, before I start copying all the images from my memory cards.

If one of my batteries has more than a 40% charge, I use it first to avoid charging too often. There's a rumor that Li-ion batteries can be charged up to 400 times before they start to lose their excellent capacity performing as the power for a dSLR.

Now to perhaps a critical question. How many shots do you tend to take on a regular photoshoot?

When I shoot football games, I usually end up with around 250 to 300 shots (one battery is good for 1000 shots on my old D300). I shot a fashion show last weekend and I shot a four shots of each model, one walking toward the camera, one away and two shots as the model posed in front of the photographers gallery, one three quarter and one head and shoulder. At the end of the night I shot a little over 400 shots of ten different designers work. I still had 17% left on my first battery. Since the lighting was uneven, I was constantly checking my shots using the LCD, not a good way to conserve battery power and not something I do as a rule. Usually once I have a good meter reading and white balance, I just shoot until I'm finished with the assignment.

So, recharge as little as possible after or between shoots by keeping one 100% battery in your battery grip. Recharge once your battery is between 20% and 10%.