Using your DeWalt DCBP520C battery is a breeze. First, make sure you charge the 5Ah Powerstack battery with the included charger before the first use. Once charged, simply insert the battery into your compatible DEWALT 20 - Volt MAX tool. The 3 - LED fuel gauge system will show you the battery's charge status, so you know when it's time to recharge. When it comes to maintenance, keep the battery in a cool, dry place. Avoid exposing it to extreme temperatures. Also, don't over - discharge the battery. If you're not going to use the battery for a long time, it's a good idea to charge it to about 50% and store it. Remember, this battery comes with a 90 - day money - back guarantee and a 3 - year free service contract, so if you have any issues, reach out to DeWalt's customer service.