The Toshiba PA3399U-1BRS is one of the most popular laptop batteries on the market, and is used for many of Toshiba’s Satellite and Tecra series of laptops.

The PA3399U-1BRS is a 6-cell lithium-ion battery. Lithium-ion technology works by moving lithium ions from a negative electrode to a positive electrode when running from battery power, or discharging. It works in reverse when charging the battery, moving from positive to negative. One of the main advantages of lithium-ion batteries is that they do not exhibit the “memory effect” common in older technologies, in which a battery could not charge to full capacity if it was not properly discharged often.

The Toshiba PA3399U-1BRS has 6-cells, which gives it a longer life than those with fewer cells. 6 cells is usually the current minimum, with some batteries offering 9 or more cells. The battery has a capacity of 4000 mAh, which translates to roughly 3.5 hours of battery life, though this can vary depending on different conditions. The unit is capable of recharging in around 4 hours when the laptop is off, and around 12 hours when the laptop is on. If the laptop is running at full power, especially when running intensive applications, the battery may not recharge. This is not a limitation of the battery, but more of a limitation of the laptop.

The Toshiba PA3399U-1BRS is very compact and lightweight. It measures 0.7 inches by 8.13 inches by 2 inches, and weighs only 11.4 ounces. This makes it ideal for portability, while still maintaining excellent battery life.

When buying a replacement for a Toshiba PA3399U-1BRS, buyers have many options. While buying directly from the manufacturer is one option, many online retailers offer compatible batteries at a much lower price. It is important to find a reputable seller who offers a satisfaction guarantee, but buying compatible batteries can save a significant amount of money, and give the same performance and quality one would expect from an OEM battery.