| 摘要 |
<p>A battery-powered electrical device (1) comprising a rechargeable battery pack (3) and a switchable voltage drain (5, 7), the battery pack (3) containing a set S of individual cells (31) in series connection, the set S having a cardinal number N greater than two, each cell (31) being characterized by: a nominal voltage Vbat; a minimal permissible voltage-value Vmin; a voltage-value Vend at which it is desirable to terminate discharge of the cell (31), whereby: the set S is divided into a number of mutually exclusive subsets si of cardinal number ni, whereby 0 < ni < N, at least one cardinal number ni is greater than 1, and the sum of all the cardinal numbers ni is equal to N; ni≤n, where n is the largest natural number satisfying the relationship: n < (Vbat - Vmin)/(Vbat - Vend); the device (1) comprises means (9) for measuring the series voltage Vi across each subset si, and interrupting the switchable voltage drain (5, 7) if the condition: Vi≤ni x Vend is met in any of the subsets si.</p> |
