Bosch Rexroth Nexo, Руководство пользователя

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Nexo cordless Wi-Fi nutrunner
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3.1.6 Nexo battery system
3.1.6.1 Lithium-ion batteries - Good to know
Cell voltage
The voltage of an individual battery cell is referred to as cell voltage. The higher the cell voltage the less
individual cells are required for a battery with high voltage. Lithium-ion cells feature high cell voltage. In
comparison with NiCd batteries, lithium-ion batteries require less cells.
Energy density
The energy density is the measurement of the amount of energy that can be stored in a cell per weight
unit. Cells with higher energy density respectively weigh less at similar storage capacity. In comparison
to cells based on nickel, lithium-ion cells offer a considerably higher energy density.
Memory effect
The term “memory effect” describes a loss in capacity that may occur at NiCd batteries. In case of fre-
quent partial discharge, parts of the electrode substance are not "used". This way, crystalline formations
occur, considerably impairing future discharge of the affected electrode substance or even blocking it in
extreme cases. This effect does not occur in lithium-ion batteries. Independently from their charging con-
dition, lithium-ion batteries may be charged at any time without damaging the cells.
Lithium properties
The properties of lithium, the lightest solid substance in the element system, enable the design of lighter
means of energy storage. However, lithium is highly reactive with other substances. A burning lithium-ion
cell is a metal fire. As lithium leads to a highly exothermic reaction with water, fires have to be extinguished
with a substance suitable to extinguish metal fires like sand or salt.
Lithium-ion batteries are generally classified as hazardous. During transport, the transport regulations for
hazardous material apply.
3.1.6.2 Nexo slide-in battery pack
Fig. 3–6: Nexo slide-in battery pack
Battery management system
This electronic module contains protection and diagnostic functions such as the charge level indicator
and balancing. Nexo battery packs offer an intelligent battery management system with individual cell
monitoring, cell balancing, short circuit protection and intelligent communication. The battery manage-
ment system monitors the temperature as well as the capacity of the battery. Uneven charging conditions
of cells are balanced by the cell balancing function. This function is particularly activated if a cell exceeds
its maximum or minimum voltage range.
1 Battery management system
2 Lithium-ion cells
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2