Let's charge it!!!
At first you shoul think about quantity of charge elements. In my example you can see 4 charge elements. Elements should have some space between each other.

So, let's begin construction of first element. The best way is to begin from the distant element. This element would be like a base for other elements, we need just to change perspective. Unite 3 ellipses (like on a pic). Way of gradient control form of element.

The same thing was in the first part of this tutorial with "+" ledge. Set the Gradient paying attention to light, shadow, semi-shadow, patch of light and reflex. Width shoul suite well.

But that's not finish. Also, we should make element more accurate. Put patch of light on the right side of the element.

One more patch light make corners smooth.

Under patch light put darker, transparent object. It will make effect of concave form.

Also, we shoul make patch light more strong on the side.

Our side began smooth. At first look the elements is finished, but, as I said, realistic effect contain many small features. That's why, i'll make this side more soft.

As you can see, this object really finished view of our charge element =)

Now put patch of light on the side of element. Then we need to group all the element layers and put new object inside our empty battery.

Copy and paste first element. Resize new element to make it closer to view. Transform it paying attention to perspective.

Copy and paste second element. Repeat the same actions. The main thing is to collect all the charge elements in one virtual tube =)

And the same things for last charge element. Now i'm closing Illustrator and export my battery to Photoshop.

Also I decided to put (Q) logo on my battery =) Transform it like it lay on the tube: Free Transform->Perspective/Warp. Then in layer options set Outer Glow, choose the best glow color for you (in my case it's green-blue) and set blending mode to Hard Light.

At this dark background I can show you where I decided to draw more light. I choosed most ledged parts and using brush and eraser I made these patch lights. In different places I used Gaussian Blur. It will make our patch lights more photo-realistic.

Unite all the layers put correction layer with Levels. Set parameters of Levels to make your image deeply and colorful.

Finaly, we should put some shadows (this is example made by black brush and smooth eraser). Well, our battery finished! =), I hope the result is fine.