Unfortunately, rechargeable batteries don’t last forever.  There’s a good chance your Makita drill will outlast the battery or batteries that came with it. (Although, the newer Li-ion batteries are rated for thousands of cycles and our choice for best 18v cordless drill comes with two, and so should last for a decade even with regular use.)

If it’s time to replace your Makita cordless drill battery, here’s what you need to know.

Physical compatibility

Most drill manufacturers try not to change how the batteries physically connect to the drill and where the battery electrical leads connect to the drill. There are many benefits (both for the manufacturer and the consumer) to keep these the same.  But occasionally the manufacturer will see a greater benefit in making a change.  And Makita did just that when they moved to Lithium ion batteries.  It was a good time to make a change for reasons noted below.

But here’s what you need to know.  You either have the stick (or pod) model or the slide model.  Obviously, one doesn’t work with the other, but for the most part each type will work with all the various models.  If you purchase a non-Makita battery it may only fit certain model numbers, so make certain yours is listed.

Battery Chemistry

There are three types of rechargeable batteries: Nickel Cadmium (NiCd), Nickel Metal-Hydride (NiMH), and Lithium-ion (Li-ion).  That’s in order of oldest to newest and generally better.  There are subtle differences in how these batteries behave.  I did an article previously on the differences between NiCd and NiMH batteries.  Here’s the bottom line:

NiCd and NiMH batteries are close enough chemically to replace each other.  There are some electronics designed to work specifically with one or the other type, but Makita designed their tools to be compatible, specifically so you can upgrade from NiCd to NiMH.

Battery Capacity

The capacity of a battery is measured in amp-hours or Ah.  Amps are a measure of current, so amp-hours is measure of current over time.  A 3.0 Ah battery will deliver 1 amp for 3 hours or 3 amps for 1 hour.  Energy is amps * voltage.  So a 3.0 Ah 18V battery has more capacity than a 3.0 Ah 14.4V battery.

But among batteries of the same voltage, you can compare Ah like apples to apples.  A 3.0 Ah battery has twice the capacity of a 1.5 Ah battery.

My Recommendations:

* If you have a NiMH or NiCd 18V Makita model you should get a NiMH replacement like this one.  There are some other models on Amazon and other places, but this one fits all the NiMH and NiCd 18V models, it’s made by Makita, has received only positive reviews and is offered by Amazon at a great price.  There are 3.0 Ah models like this one, but it’s not made by Makita and currently has no reviews.

* If you have an 18V Li-ion Makita drill you have two options.  There’s the 1.5 Ah model and the 3.0 Ah model battery.  The 3.0 Ah model has twice the capacity for only about $14 more, so it’s got the value.  But it’s heavier.  One of the best features of the best 18V cordless drills is the light weight.  Since this is a replacement battery, you know how long the battery lasts and whether you need the extra capacity or could deal with half the capacity.  Make your decision accordingly.

This entry was posted on Saturday, April 24th, 2010 at 12:39 pm and is filed under Cordless Drills. You can follow any responses to this entry through the RSS 2.0 feed. You can leave a response, or trackback from your own site.