Among battery-driven power management solutions, there are numerous alternatives because competing battery chemistries differ significantly with regard to cost, performance, safety and durability. When configuring a power management solution for a wireless device, the first step is to carefully evaluate application-specific performance requirements and address certain fundamental questions that can dictate the type of battery chemistry to be considered. Critical design considerations include size and weight requirements, energy density, capacity and high current pulse requirements (if applicable), access to a reliable AC power source (which is essential if a rechargeable system is being considered), and environmental factors, such as temperature range, moisture and humidity. Also to be considered are possible safety issues that could arise if the battery is subjected to extreme shock, vibration, puncture or breakage. If the device must be transported by air and the battery is considered hazardous goods, then it is important to know what shipping restrictions may apply with regard to IATA or national and sometimes international regulatory agencies. If the wireless device is handheld and intended mostly for personal use, including most cell phones, PDAs, or bar code and RFID scanners, then the most cost-effective power management solutions typically involve the use of rechargeable batteries. The newest generation of rechargeable battery chemistries offers significantly enhanced capacity for longer service life with reduced memory effects, allowing these newer systems to be recharged hundreds or thousands of cycles. This makes battery access and replacement less of a critical design factor than in the past. By contrast, if the wireless device is intended for long-term use in remote locations with no direct access to AC power, then it is very likely that a primary (non-rechargeable) battery will be required.