This general information for the list is taken from a daily Email I receive as part of my web subscription to Smart Computing magazine. I recommend the subscription for blind users since it is easily accessible with screen readers, and the annual fee for twelve issues plus other features is less than $20. Full articles can be transferred to the Bookport for reading at your convenience. The web site is currently offering a free trial subscription. www.SmartComputing.com Smart Computing Daily Information For Wednesday, August 16, 2006 Daily Tip: Li-Ion Battery Advice Avoid frequent full discharges. The reason this is an issue is because performing frequent full discharges puts additional strain on the battery. Several partial discharges with frequent recharges are better for Li-Ion batteries than one deep one. Recharging a partially charged Li-Ion battery doesn't cause harm because there is no memory. (In this respect, Li-Ion differs from nickel-based batteries.) Short battery life in a notebook computer is mainly caused by heat rather than by charge/discharge patterns. Batteries with fuel gauges (notably notebook computers) should be calibrated. You should calibrate these batteries by applying a deliberate full discharge once every 30 charges. (Running the pack down in the equipment does this.) If ignored, the fuel gauge will become increasingly less accurate, and in some cases, it can cut off the device prematurely. Keep the Li-Ion battery cool. Avoid a hot car. For prolonged storage, keep the battery at a 40% charge level. Consider removal. Perhaps you should think about removing the battery from a notebook when you're running the computer on fixed power. This isn't because the battery will overcharge; it's to save the battery from the extra heat. (Some notebook manufacturers are concerned about dust and moisture accumulating inside the battery casing, whereas others warn that in the event of a power outage, or if you disconnect the notebook forgetting that the battery isn't there, you may lose data.) Avoid purchasing spares. Don't just buy Li-Ion batteries for later use. You must observe the manufacturing dates. Also, don't buy old stock, even if it's sold at clearance prices. If you have a spare. If you happen to have a spare Li-Ion battery, use one to the fullest and keep the other one cool by placing it in the refrigerator. (Just make sure you warm the battery to room temperature before use.) Do not freeze the battery. For best results, store the battery at a 40% state-of-charge. Mike Justice, www.MPNHome.net