Pololu 3.3V Step-Up Voltage Regulator NCP1402 This compact step-up (or boost) regulator generates 3.3 V from voltages as low as 0.8 V and delivers up to 200 mA, making it perfect for powering small 3.3 V electronics projects from one or two NiMH, NiCd, or alkaline cells.
SparkFun Variable Load KitThe SparkFun Variable Load Kit is a quick-to-assemble board designed to allow users to draw a specific amount of current from a voltage input. This kit can be used to test stability of the power supply under various loads, battery lifetime, safety cutoffs and other design elements.
SparkFun DC/DC Converter Breakout This is a breakout board for our non-isolated, 6A DC-to-DC Converter Module.
PowerBoost 500 Charger - Rechargeable 5V Lipo USB Boost @ 500mA+ PowerBoost 500C is the perfect power supply for your portable project! With a built-in battery charger circuit, you'll be able to keep your project running even while recharging the battery!
SparkFun Sunny Buddy - MPPT Solar Charger This is the Sunny Buddy, a maximum power point tracking (MPPT) solar charger for single-cell LiPo batteries.
Adafruit Pro Trinket LiIon/LiPoly Backpack Add-On If you have a Pro Trinket you probably know it's the perfect little size for a portable project. This LiPoly backpack makes it really easy to do!
Power Cell - LiPo Charger/Booster The PowerCell board is a single cell LiPo boost converter (to 3.3V and 5V) and micro-USB charger in one.