After the standard NiCd battery had flabby made in Bosch cordless and I already found unacceptable from waste avoidance reasons why to buy a complete replacement, alternatives were announced. The decomposition of the old battery packs (Torx screws) revealed: by spot welding of the solder tails are connected in series, not individually monitored or buffered NiCd batteries - due to long storage and flat cycles deeply discharged irreversible. The size unfortunately quite unusual (thicker than AA but shorter), a conversion to Eneloops therefore eliminated. Original replacement was firstly expensive and secondly, (inexplicably) is still performed in NiCd chemistry, which is why I chose the here discussed exchange product with more capacity and NiMH cells.
The delivered package was slightly longer than the original, possibly to another round batteries to provide space. Inside can be found ten brand cells in series incl thermosensor -. As the original predecessors. At the fit there is nothing to complain about, neither the snapping behavior in screwdriver still on the charging station was open to criticism.
After the charging cycle (of an hour took to complete) showed my PSR significantly more punch, I'm assuming that the cells of quite fresh manufacturing originated and low internal resistance exhibited. Since I have not carried out a single cell tests, I can only guess whether the promised 3Ah be achieved: The breath is the duo with conventional screwing anyway as soon not and percussion drilling should be the small device with something puny chuck or spindle bearing yes anyway not particularly expect extensively.
Would remain the only weak point:
During the reviewed products definitely not is a so-called L (ow) S (elf) D (ischarge) variant as 8er example of Sanyo eneloop under the name Sanyo battery Mignon / AA HR 3UTGA min. 1900mAh type 2000mAh Bonus Pack 8 + 2 Batteries Battery boxes are available. What does this mean for the user: He should charge the pack in its own interests after work always full and ensure that is recharged at regular intervals, at the latest, as soon as the screwdriver is weakening as the shaft rotates. A memory effect is not to be feared in NiMH chemistry, but a significant self-discharge, which is between 15 and 50 (!) Percent per month.
Although the discharge curve to end capacity is somewhat flatter, still risking a deep discharge with destruction of the battery, if you "forget" to drill for months in the tool cabinet.
In conclusion therefore, because of the quite high self-discharge only four-star Amazon for an otherwise flawless product.
Enjoy Yourself!
PS: According to the latest findings in assembling a garden shed in which an entire day in wooden screws 4x50 format were to rotate with Torx drive into pre-drilled pine and spruce wood panels, I can only praise the perseverance of the battery pack. Only hardcore home improvement are here to hold a second power pill, the rest of loads during the lunch break on again and is happy about a resurgent drill.
