The charge times posted on our site are all "real", meaning they are based on actual tests, but they are under ideal conditions: cool and cloud-free.

Clouds, haze, shade, heat, dirt and panel angles will all reduce charge rates.

For best performance, be sure to:

• Place the panels outside - you will get half the power and often much fewer hours of direct sunlight behind a window
• Point panels directly at sun - once the panels get past about 45 degrees, power production drops steeply
• Minimize shading and make sure nothing is covering any part of any cell

If it is cloudy, extremely hot or you have obstacles shading the panel, expect charge times to increase, sometimes quite dramatically. You can decrease charge times by increasing the size of your panel or adding a second panel.

If you still think the battery is charging abnormally slowly, email technical support with:

• Description or picture of your product and battery (model number is on the back of battery)
• Description of the problem and what you've tested
• Order number for warranty purposes
• Best shipping address