Lithium Ion batteries are becoming ever more popular in today’s power tool world. We get a lot of questions each month about this battery technology:

  • How reliable are these batteries
  • Are they actually better
  • What are the downsides to these batteries
  • Is it true Lithium Ion batteries burst into flames

We do have a section on batteries that explains all the types and gives a brief over view of each type  under our – All About Batteries. However, we thought it was important to cover Lithium Ion batteries in more detail so you can understand this battery technology and therefore protect your investment for the long term.

Let’s start out with some basics. What are Lithium Ion batteries and are they the same as Lithium batteries? In short, they are different. A Lithium Ion battery can be recharged while Lithium can not be and that’s the main difference. The chemistry that makes up these different batteries is different and that is due to more stability needed with a rechargeable battery.
There are a lot of Pro’s and Con’s to Lithium Ion batteries:

Some of the pro’s are:

  • Very light compared to other types of rechargeable batteries of the same power
  • Stores more power size for size. A typical Lithium Ion battery can store about 150W in 1 Kilogram of battery, while a NiMH stores around 80-100W. Also, a Lithium Ion can store more energy, about 3.7V compared to 1.2 V for NiMH or NiCd. This means a Lithium ion can use a single cell rather than multiple cells.
  • They hold their charge longer. A Lithium Ion will loose about 5% per month and up to 1% a day sitting on your workbench, while NiMH will loose about 20% or more per month.
  • Lithium will work till the last pull of the trigger while other will slowly lose energy before they go dead.

Some of the Con’s are:

  • More chances for a Lithium Ion battery to fail since they need an on board computer to manage the battery
  • Even if you don’t use the battery it will degrade
  • They are sensitive to extreme high temperatures and will degrade quicker.

While these are the con’s, they hold true for older Lithium Ion batteries.  Today technology has improved and the con’s come less into play.  Manufacturers have figured out ways to improve this technology and can now produce a very reliable battery with less defects.  As we discussed above, manufacturers have small on board computer systems built in for safety features. If you over charge a battery, you can cause it to explode.  In addition, you also run into problems when the charge is to low. You need to remember this when you store batteries and be careful not to let the power drop to low in the battery. Have you ever talked with someone or read something online that illistrates people complaining they have had problems with their Lithium ion battery? They blame it on the manufacturer, saying the tool was shipped with a bad battery that won’t charge. While it is true sometimes it is the manufacturer’s fault, it can also be the distributor’s fault.  Some distributors don’t have high turn over, so their tools just sit there. Well, we know these batteries lose power sitting in storage, and if the power goes below a certain rate, the small chip system on the battery says not to charge. These stories still float around, but they are based on the older versions of the Lithium Ion batteries.  Now a days, manufacturers will not charge the battery and have better safety features to prevent this if the battery is charged.  To prevent this problem, always buy from a well known distributor that you know has high turn over.  This way you are buying a “fresh” battery.  Tylertool.comis one of the largest power tool distributor’s around that moves a large amount of inventory.  So when you are looking for a kit or even a battery, take a look at because you know you will always be getting a power tool that was recently manufactured and not something sitting on the shelf.
Some Tips

Storage – When storing a Lithium Ion battery, you have to be careful. As we discussed above Lithium will hold a charge for a long time, but when sitting around the charge will become less. If the charge drops below the safety level where the battery can be safely charged, the charger will not charge the battery and now it will be dead with no way to bring it back to life.  So when you store these batteries make sure you have a full charge and take them out every other month to use.  Just to make sure it doesn’t fall below the safety level. Also, store you batteries in a cool dry place.

Power – Sometimes a Lithium Ion battery needs to be charged between 2 -10 times before it takes a full charge. Remember to always charge your first charge over night to make sure it has maximum power for the first time.

Memory – Lithium Ion batteries do not have a memory.

Balance – Occasionally leave your battery on the battery charge over night. This will help maintain a proper balance. This can be done about once a week.