[HH] universal power tool battery

[Greg London]

I bought a bunch of cordless power tools last year,
ended up getting makita 18v lithium ion tools.

Their charger will fully charge a 18v, 3amphour battery in 30 minutes.
And I can testify it delivers on that spec.

http://www.makita.com/en-us/Modules/Accessories/AccessoryDetails.aspx?ID=34111

Not sure how li-ion compares to nimh, but makita is considered
a pretty good toolmaker, and li-ion is the technology they're
using now, so...

I have beat the crap out of their tools and they keep kicking ass.

I keep wondering if I could just plug two batteries in series
and use them to power their 36volt circular saw.
The 18v saw will cut 2x4, but the 36v uses a bigger blade and
has more bite.

What little I've read says the tool somehow communicates with
the battery, or the battery communicates with the tool.
So, I wasn't sure about putting them in series.

I also keep wondering about some sort of converter
because makita doesn't have certain cordless tools,
like an oscillating multitool for doing plunge cuts.

http://www.tylertool.com/bosch-ps50-2b-12v-max-cordless-lithium-ion-multi-x-carpenter-kit/bshnps50-2b,default,pd.html?ref=pricegrabberPS50-2B&zmam=31282435&zmas=41&zmac=479&zmap=PS50-2B


Greg



> Ever been annoyed that every cordless power tool you own requires a
> different, incompatible battery? What's worse is that for each tool you
> really need multiple batteries, and you have to replace them every few
> years. This can be a big problem if the manufacturer discontinues the
> product line and makes no more batteries, or decides not to update the
> product line to use newer battery technologies.
>
> Manufacturers apparently think this approach will maximize profits by
> locking customers into their product line, but what actually happens is
> that you "buy-in" to one or two tool families, and then ignore the
> others, even if they happen to offer a unique tool. If a suitable choice
> isn't available in one of the families I already own batteries for, I
> just buy a corded tool, or nothing. The battery overhead cost is too
> high, and too inconvenient if you need to pack and take your tools
> somewhere (batteries and chargers take up a lot of space).
>
> Several years back there was some company with a promotional video on
> YouTube that had cobbled together a "universal" power tool battery. They
> standardized on the Ryobi ONE 18 V battery. They then built adapters for
> various other product families by taking a battery pack from the other
> vendor, removing the cells, and fitting a socket for the Ryobi ONE to
> the bottom of the hollow pack.
>
> The end result looked ungainly, ugly, and by moving the real battery a
> few more inches away from the tool body, probably threw off the balance
> on many tools. I'm sure on some tools it wouldn't even have the space to
> fit.
>
> I was hoping they'd replace the makeshift adapters with some custom
> built adapters that could be substantially smaller. Also, switching to a
> "flat" rectangular pack instead of the Ryobi ONE, which has a stem,
> would result in an adapter that would only need to separate the tool
> from the battery by a fraction of an inch.
>
> But they apparently couldn't commercialize the technology, as I never
> saw it again.
>
> I've rebuilt NiCd packs (usually replacing the cells with higher
> capacity NiMh cells), but a while back I decided not to spend any more
> money on NiCd/NiMh technology. I've pondered rebuilding the NiCd packs I
> have with LiOn, but aside from mechanical differences in the cell size -
> getting fewer, but bigger 3V cells to fit into a box made for a pile of
> 1.2V NiCds - you also need to find room for a protection circuit (under
> and over voltage and current limiter), and add a multi conductor
> connector so each LiOn cell can be individually charged and balanced.
>
> I've since upgraded to vendor supplied LiOn batteries for the tool
> families where they are available, but for some they aren't. I've
> considered the adapter approach...for a while I even looked for a busted
> as-is cordless drill on eBay with the thought of chopping off the
> battery socket to make an adapter.
>
> In the end I took the quick hack approach. I took one of my end-if-life
> NiCd packs, hollowed it out, drilled a hole in the back and threaded
> through some 16 AWG zip cord wired up to the battery pack contacts. On
> the other end I put on alligator clips, which mate nicely with the not
> quite 1/4" tabs on my 24V Ryobi LiOn pack.
>
> This brought new life to a line of Tack Force (Lowes house brand) yard
> tools that were abandoned by the vendor, and a Black & Decker chain saw
> (which uses a 99% identical battery to Tack Force (clearly produced in
> the same Chinese factory), with just enough difference to make them
> mechanically incompatible; a prior hack to the saw's battery socket
> allowed the Tack Force batteries to fit).
>
> So the end result is a battery on a short cord. Makes the tool lighter,
> but the battery needs a belt clip or something to get it out of the way.
>
> Today I ran across a commercial version of this:
>
> 18V Nicad Battery Belt with Adapter and Charger
> http://www.mcmelectronics.com/product/22-14562&cid=prodCrossSell
>
> See the cheesy video for a demo.
>
> Their solution to the dangling battery was to stick it in a "fanny
> pack." (A backpack version is also available.) Nice that it comes with a
> 5 Ah battery (compared to the 1 to 2 Ah typical of most tools), but I
> don't get why they'd use old NiCd technology, particularly seeing as
> they are asking $200 for this battery plus adapter kit. (This kit
> happens to come with a Ryobi ONE adapter, but Dewalt and Craftsman
> adapters are also available.)
>
> I think in the end my components are better. Aside from the electrical
> performance advantages of LiOn, it is lighter, and even in a belt I'd
> rather carry a smaller, lighter battery, and have a couple of them that
> can be cycled through the charger. What my solution needs is a belt
> holster of some sort, and a proper socket for the Ryobi pack.
>
>  -Tom
>
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