Sign in or register to get started. low batteries might effect the accuracy of your scales. Always use the same scales!! Change the batteries and hopefully your weight will be more accurate. i found that it does with my scale. it showed that i gained weight when it was low. i always keep a spare because i weigh myself every morning.
Lithium-ion batteries charge faster, last longer and have a higher power density for more battery life in a lighter package. The weight of a Lithium-ion battery depends on the size, chemistry, and the amount of energy it holds. A typical cell weighs about 30-40 grams. Cells are packaged together to make a battery pack for a device.
The first step in calculating the weight of a lithium ion battery pack is to determine its capacity in amp-hours (Ah). This is typically provided by the product specification for off-the-shelf batteries or by dividing the total energy (in Watt-hours) by the nominal voltage if designing custom packs.
As we've already seen, lithium-ion batteries have much higher power densities than their predecessors. But they also have much higher specific energies - typically 150 Wh/kg compared to 50 Wh/kg for lead acid batteries and 70-90 Wh/kg for nickel metal hydride types.
Weighing in at around 50 grams each, this totals up to 714 kilograms (1,574 lbs). Lithium ion batteries can weigh as little as 3g/Wh, or as much as 8g/Wh. A typical laptop battery weighs between 80 and 120Wh/kg, which means it weighs between 240 and 960g (or .5 to 2 pounds). A typical smartphone battery might weigh around 20-40g.
Lithium ion batteries have an energy density of around 160 Wh/kg, which is 0.16 kWh/kg. This 12:0.16 ratio translates to an equivalent volumetric density of 76.8 kWh/l. The Tesla Model S has a battery pack with a capacity of 85 kWh and weighs 540 kg; this gives it a volumetric energy density of 0.39 kWh/l - about 5% of the equivalent for gasoline.