Like iMedic has mentioned it may be a bad battery or possibly a battery that discharged and entered into a protective sleep mode state. Batteries from the factory should not read 0v or be drained completely. They are usually charged to about 40% when they leave the factory. If a lithium ion battery sits for an extended period of time it may slowly loose it's charge, especially in harsh environments such as too hot or cold. Most lithium ion batteries actual contain a protective circuit that will put the battery in a sleep like state if its voltage drops below a certain voltage. This is to help protect the battery from damage caused by over discharging, overcharging, and other factors that could cause damage to the battery. If a battery reads at 0v and is in this sleep state after buying it, I would recommend trying to return it for a different one. If you can not return it then you can try boost charging the battery. By boost charging you are supplying the battery with a higher voltage for a short period of time to wake the battery from the protective sleep state. Kind of like jump starting a car battery. This can be done by either buying a special charger with the boost function or you can do it manually with the right supplies. Once the battery is awakened you then proceed to charge it with its original charger. I would try exchanging or replacing the battery first and if you can't I would then as a last resort boost the battery. I can further explain how to do it manually if needed, but keep in mind it can be very dangerous if not done properly. Many people are not aware of the protective circuits in these batteries and end up throwing away a perfectly good battery just because it reads at 0v, when in reality they have a healthy battery that likely has just sat too long without use and entered into the protective sleep mode. You may also sometimes just have a damaged battery that needs replaced. Hope this is useful for someone.