Almost anyone who uses rechargeable batteries has heard of the Memory Effect problem. The symptom is that the battery appears to be fully charged but discharges quickly after only a brief period of operation. This problem is generally the result of rechargeable batteries not being fully discharged between charge cycles that they remember the shortened cycle.

Sometimes, much of the lost capacity can be recovered by a few deep discharge cycles, a function often provided by NiCad battery chargers. Memory Effect occurs primarily in NiCad batteries. NiMH batteries are almost never affected and Li-Ion batteries are NEVER affected.

If treated well, NiCad batteries can last for 1000 cycles before capacity drops below 50% of original

How to Avoid the memory effect

With 3 - 5hr battery packs, ensure each new battery gets an initial charge at least twice. Initial charges are usually around 6 to 8hrs

Ensure your battery is fully discharged before re-charging. A discharged battery is when the product it is powering is deemed useless

Do not discharge your battery pack to deeply. Discharging to absolute zero will make your battery useless. 1v is the minimum recommended voltage

Charge your battery fully Not any less or any more. Remember that 3hr chargers do not switch off themselves. The use of an electrical timer will ensure over charging will not occur

Avoid charging hot battery packs and store in a cool dry place out of the sun

Always store a rechargeable battery charged

Battery Charges

3 - 5hr chargers do not switch off once the battery pack is charged. Overcharging will destroy the life of the cells

You must remember to switch them off or use a general purpose electrical timer

Fast chargers, range between 10 and 60min to charge

When the cells are electronically determined as being charged (by monitoring current and temperature ) the charger will automatically switch to trickle mode so as to not over-charge the cells

Hints and tips

Follow the usage tips as described earlier regarding battery life & condition

To maximise the run time from your batteries, select the right gear if available and keep the rpm up

Only use the Hammer function when absolute necessary

Do not over tighten the chuck and keep clean of dust & dirt

Keep battery contacts clean

Avoid dropping battery packs

Always let the accessory do the job it is designed for, never apply too much pressure to the tool.

Applying extra pressure will only drain the charge from the battery and risk damaging the tool

Whenever changing any accessories always remove the battery from the drill

Never dispose of rechargeable batteries into fires

Never modify batteries or chargers to operate other appliances

When drilling, always check the reverse side of the material

Check before drilling or screwdriving into cavities for hidden pipes and electrical wires

Always switch off chargers when not in use

Avoid wearing loose clothing when drilling

Wear eye protection when drill masonry overhead