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Charge Your Batteries Right And Avoid Expensive Replacements

Following the correct charging and discharging methods for your cordless woodworking tools can enhance the life of the battery and save you from buying expensive replacement.

First thing go through the instruction manual on battery care. Not all chargers are the same. For example, DeWatt designs several of batteries and chargers in such a way that the battery can be left on the charger for maintenance and equalization cycles.

How To Charge Li-ion Batteries

1. Li-ion batteries like partial discharges. You do not have to wait for them to fully discharge. Top them up whenever you get the chance.
2. Li-ion batteries like partial charges. You don't have to charge them till 100% before using them. In fact, they go through maximum wear and tear and stress when charging 90-100%. By charging them to less than full capacity you will extend their life.
3. Li-ion batteries do not like complete discharge. Do not discharge below 20% when you can help it. Stop using the tool when it shows signs of weakening in power and slowing down. Re-charge the battery at this point.
4. Do not charge or discharge in very hot conditions like over 40°C.
5. Do not leave the Makita drill battery in the charger for very long after fully charged.
6. Discharge a Li-ion battery periodically. They have a shelf life and they stay active for longer when kept in use.
7. Charge to 30-40% before storing.

Note: A lot of cordless woodworking power tools don't have a built in battery meter that shows the amount of charge left in the tool. Even the ones that do give a rough idea. Not like the exact percentage that we are used to seeing on our computers and smart phones. So its difficult to tell when the battery is 20% or 90%.

You will either have to use an external meter. They can be found cheaply online. Or as we have mentioned, just stop using the tool when it slows down and put the battery on charge.

How To Charge Nickel Based Batteries (NiCd and NiMh)

The main difference between NiCd and NiMh batteries is that NiMh does not suffer from the 'memory' problem as much as the NiCd version. This means they do not have to be deep discharged.

1. Charge the battery when the performance of the tool diminishes. Do not try to drain the battery.
2. Topping up and partial discharge is OK. Discharge till the tools starts slowing down once in 20 days or 30.
3. Can be kept in the charger to maintain charge if the manufacturer allows it. Check the instruction manual for this information. Many manufacturers make their chargers like this since Nickel based batteries lose their charge very fast.
4. Repeated full discharges are OK (till the point where the tool starts slowing down.) They don't harm the battery. To deep discharge and recondition the battery, take it out at this point and put aside for a day or two.
5. Check if your charger has a 'reconditioning' or a deep dis-charge mode. This is also know as a 'maintenance cycle'. The better cordless tools have chargers with the ability to run the batteries through a maintenance mode.
6. Avoid charging in very hot locations. i.e. above 40°C.
7. Many manufacturers will recommend completely discharging your NiCd and NiMh batteries before storage. Not much point in storing them in a charged state either since they lose their charge pretty quickly.

Best Practices For Long Battery Pack Life

Should I completely discharge my tool battery before charging it?

No. Charge the battery as soon as you feel the power and speed of the tool considerably reduced. Draining the battery completely can damage it. people sometimes try to do this by lying up the trigger switch in the on position.

What is 'Memory' and does my wood working tool battery have it?

Memory is a condition in which a battery 'forgets' its full capacity to charge and deliver. But this happens in low drain devices. For memory effect to set it, the battery must be drained at the same small rate every time and to the same level i.e. partially. This very rarely happens in wood working tools. The rate of discharge is high since these are high load machines.

Memory effect happens usually in devices that consume less power like cordless phones and electric shavers. Secondly, tools are rarely discharged to the same level on every usage. And the rate of discharge is not uniform. It varies constantly with user handling, intensity of the job and the material it is being used upon.

Therefore, power tool batteries rarely see the occurrence of memory effect. If your tools have Li-ion batteries, memory effect is completely ruled out.

Can I leave the batteries plugged in the charger when not in use?

Read the manual and instructions that came with your tool. Usually it is advisable to take out the battery from the charger after its fully charged. Do not leave it in for more than 12 hours.

If you are not going to use the tool for some time, its better to store the battery in a partially discharged state (40%-50%) in a cool place. However, some manufacturers will allow you to keep the battery in the charger. They have designed their chargers specifically for this purpose for maintenance of the Bosch power tool battery.

My battery run time is low. What can I do to improve it?

You can run your battery through a couple of proper charge cycles. If the battery isn't damaged or beyond its usable life span, this should help increase the run time of your cordless wood working tool.

• Discharge the battery by using the tool till it begins to slow down substantially. Do not completely drain it. Do not tape the trigger switch in ON position.
• Leave the battery out of the tool for a couple of hours till it cools down.
• Charge the battery for a full 8-12 hours in a cool place. Repeat this process 2-3 times.
• If your battery still doesn't show any improvement in run-time, consider buying a replacement.

Does ambient temperature effect the batteries?

Yes it does. Batteries stored in hot places lose their charge quickly as well as their capacity. Using a tool in too hot or too cold (4°C to 30°C is ideal) can reduce its capacity.

Similarly, a battery being charged in extremities of temperature many not take the charge fully and also suffer from reduced run-time. The reason is that when a drill battery fot Dewalt tool is being charged or discharged, there is a chemical process happening inside the battery.

Heat and excessive cold interferes with this chemical reaction, sometimes bringing about changes in the battery chemistry that last for good.

How do I dispose off dead batteries?

Never throw them in the bin. Always recycle them. Check your user manual. Many major tool manufactures support and are a part of a recycling program. You may be able to recycle your battery through them. Check with the store you bought the tool from. Look through the yellow pages or online to find the closest recycle center.

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