To get your Stanley Fatmax V20 battery back up to par is simple: There are some visible indicators of what to do, and it’s all pretty easy without special software or fancy tools. Start by removing the battery from the cordless tool; it come off easily.
First, detach the battery from the cordless tool, which pops right off.
Monitoring the Charging Progress

Before proceeding to the next step, remove the pack entirely. This ensure it’s safe to charge.
The battery have a button on top that you can push to check the battery life. You’ll see the LED light up and indicate the power level in the battery. Knowing this will help you plan accordingly.

If you have half-a-battery left, for instance, it will let you get back to work sooner then if you had a fully depleted battery. You won’t need to guess; just look at the LED and you know exactly where you are.
Check the remaining charge by pressing the button on the top of the pack.
Line up the contacts, slide it on until it clicks into position, then set the battery down on top of the charger.
Place the battery onto the charger by aligning the contacts and sliding it in until it snaps into place.

It make for a strong connection without any movement. The charger instantly recognize the pack. When it does, you see a blinking green light that lets you know it’s starting to charge.
A blinking green light indicate that charging has begun, which confirms the system is working correctly.

The light stays on constantly, so there’s no question whether it’s plugged into the charger or not. How long does it take? That vary depending on the speed of your charger and the size of the battery.
For instance, a little 1.5 amp-hour battery will charge in about 45 minutes with a standard 2 amp charger (fast enough for a lunchtime break).

The charging time for both batteries is reasonable. The 2.0 amp-hour pack take roughly an hour (60 mins), which fits nicely within most workflows. Because it has twice as much juice, the bigger 4.0 amp-hour battery will take roughly 120 minutes to top off.
Just know that while the charger’s doing its thing, it maintain a constant speed so plan accordingly if you’re in a rush and grab a smaller pack instead. When the light turns solid green and no longer blinks, it’s done.

Once charged, pull out the pack and know that you have enough; solid light equals full, and you’re good to go. Remove, check, charge, wait, double-check. It makes sense and doesn’t require a second guess.
Each step is illustrated, and the lights does the talking. A solid light means finished, and a blinking light indicates it’s charging. Knowing that at a glance helps you learn what those indicators mean quickly. It’s dependable, gives you uninterrupted juice to let you get to work.