Battery Adaptor for Cordless Tool Version 2




Introduction: Battery Adaptor for Cordless Tool Version 2

Last year I posted my first instructable  for a Battery Adaptor for my old 14.4 Volt  Ryobi  cordless tool set  including flashlight, small circular saw and a drill.
First the charger went, then the batteries died, and then before I could buy replacements the company then switched to the 18V format and dropped all product support for the 14.4V line.
I purchased a new 18 Volt drill from another manufacturer in protest but it really wasn't  as good as my old one, the chuck slips when drilling and the drill clutch does not seem to handle torque well.
So this is my second Battery Adaptor  Hack to resuscitate my old tools cheaply and keep them running!
My newer 18Volt orange and white brand drill and chopsaw combo had a different battery setup than my other 18V batteries that I built my first adaptor too,  Cleaning out the garage and workbench this spring I found my other old dead 14,4 Volt battery and started hacking away....

Step 1: Deconstruct Your Battery

Take your old battery apart, save the screws, and carefully separate the metal clips off from the battery, You can dry fit the terminal end back inside to the top to see how it fits and what terminal is postive and negative.

Step 2: Prepare the Terminals

Crimp and solder a wire on one terminal, glue it in place,
Solder a wire onto the other terminal,
When cool, glue into place in the top of the adaptor.
Note what side is positive and negative.

Step 3: Prepare the Bottom of the Adaptor

Examine and measure  the top of the new battery.
Mark the width on the bottom of the battery adaptor.
Cut the bottom, cut the ends,
Remove the cut section.
Cut the back deep enough to fit the T shape on the new battery.
Pry out the tabs,
See if you can slide it in!
Cut any notchs you need,
Try again and it even locks in like it was supposed to be!

Step 4: Hack a Battery Connection

I wanted to use found items and rather than go to the store  I found a used replacement plug .
I measured the width of the connectors and figured it would work.
Once I cut the insert in two and shaved the new connectors a bit they fit in nicely.
The great part was that its really easy to attach the wires! 

Step 5: Final Battery Steps

Find out what terminal on the 9V end of the battery tester is positive ( if reversed the tester goes backwards).
Test the 18V battery to find out what terminal is positive and what is negative.
Mark the terminals so you don't get them mixed up later.
Plug in the adaptor wires ( colour coded).
Slide the battery into the adaptor.
Plug it into the tool and start working!

I 've done a lot of drilling and screw fastening with my 18V batteries in a 14.4V drill and so far no problem whatsoever with over heating or buring out. 

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    9 years ago on Introduction

    I've made a few more and used the suggestion to better colour code the wire and tape I use so I don't get the Pos and Neg mixed up....

    Callum Snowden
    Callum Snowden

    12 years ago on Step 5

    To remember wire colours for positive and negative, I usually do "Lighter colour is positive, darker colour is negative". It helps me a lot. :)


    12 years ago on Introduction
    Great site for replacing the cells with same or higher quality
    Just look for tabbed cells and for better(longer) performance get higher mAh rating.
    Hope that helps for future fixes.


    12 years ago on Introduction

    why dont you just get some replacement batteries, sub c is generally the size used. They are easy to find online and then you can replace them the same as the ones you had before, i havnt bought a new batt pack in a couple of years.


    Reply 12 years ago on Introduction

    Good suggestion and entirely possible. Do you know any instructables that show how to solder them together?  In my case the 14.4 V charger broke and I have all these other 18 V batteries around that do better if used a lot than if just left sitting and only used occasionally. Now I have 4 batteries that fit my set rather than the two original.