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Why Sub c batteries used in battery packs for drills? Answered

Is this somehow related to discharge rate? I'm trying to replace existing sub c batteries, but their price is put me off. Can anyone provide some info? If use equal capacity aa, what the difference gonna be (once again discharge rate)?
I would  really appreciate any info about this.

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Extasy
Extasy

9 years ago

Thank you reply guys.

My current battery pack contain 10 cells sub c 4/5 and rated 1.2 Ah. (it's Bosch 12V drill battery pack)

My question is what maximum current can Nicd and nimh batteries supply? From google, there is info that NiCd batteries can provide higher current than nimh, but there is absolutely no figures to confirm this.

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bloopBloopThePainterFox
bloopBloopThePainterFox

Reply 1 year ago

Look for a 'C' rating: this is the amount of current a battery can supply as a multiplier of capacity.

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mpilchfamily
mpilchfamily

Reply 9 years ago

Each battery type can come in a range of Ah ratings. The Sub C NiCds seem to top out at 2Ah while the NiMh look to go from 3.8Ah to about 5Ah. It all depends on how long you want the batteries to last and how much you want to pay for them. It looks as though Bosch used a cheaper set of batteries to build the battery pack. So going from 1.2Ah to 2Ah batteries would be a nice improvement. But if your willing to spend $5 a battery for the NiMh rated at 5Ah then you can have a huge improvement. So do you want more power for about $20 or are you willing to go the extra mile and get more then twice the power for more then twice the price?

The Ah ratings i listed are the highest ratings i could find for sale online for each battery type. They could go higher then that but i doubt it. But advances in batteries are being made all the time. Though its safe to say NiCds have pretty much reached there limits and research has moved on to better options. So just get the highest Ah rated batteries you can find/afford.

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rtrg
rtrg

Reply 8 years ago

You seem very knowledgeable so I will ask you this. I have a cordless tool set that uses a very unique design 18 volt battery pack. It is of the NECK design with 3 FLAT contacts around the NECK, FLAT to the rear. Inside are 1 sub c in the neck and 14 cells in the body, 5cells.4 cells, 5 cells stacked in a pack plus 1 equals 15. Do you know if I can buy a preassembled pack in this configuration? I have sean some with two cells for the neck. That pack will not work in my "BOX". If tis pre assembled pack is not available I might as well buy the packs from the vendor. Single cells I solder together is more $s than from the vendor. Any help welcome. reeltoreelguy@gmail.com

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ΧωρίςΌ
ΧωρίςΌ

Reply 2 years ago

Please provide detailed info where to find/purchase NiMh batteries with such high capacity (e.g. 3.8Ah and ESPECIALLY 5Ah).

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mpilchfamily
mpilchfamily

Reply 8 years ago

Buy the packs from the vendors or solder your own pack together.

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davemanchoo
davemanchoo

Reply 8 years ago

the dewalt 18v nicad cordless is rated at 400w. P=VA 22 amps
dewalt 12v nicad 240w so 20 amps.
18v li ion drill 350w. 19.4 amps
20- 25 amp max current maybe from subc batts.

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Downunder35m
Downunder35m

2 years ago

I try to explain the battery quality from the little experience I have.
All started when I got a pack of 50 "high quality OEM" AA batteries some years ago.

If you ever bought standard alkaline batteries in buk then you might have noticed that there is a big difference between brands.
And I don't mean the price.
Really good alkaline batteries are heavy!
Compare a cheap one from the discounter with a brand name one and you know what I mean.

Similar story for NiCd rechargeable batteries.
But where the alkaline often lack a thick Zink mantle the NiCd ones often come relatively dry.
Not enough electrolyte makes them much cheaper and longer lasting but also reduces their output and charging capabilities.

If a battery feels light then I just won't buy it ;)
As for actual power output:
You have the outer can, forming the negative of the battery and the inner graphite rod making the connection.
Some NiCd batteries just use metel though.
Either way, the longer and thicker a battery is the more power it can deliver.
See it like a bucket with water - the bigger it is the more can go in and come out when you need it.

Replacing the batteries of an old NiCd drill is not really worth it anymore if you ask me.
These batteries need to be constantly used to be of any use.
Storing them for weeks on end until you need the drill again means they destroy themself by doing nothing.
I would consider to invest in a Lithium Ion drill if you really need battery power.
Otherwise just use a beefy 12V power supply ;)

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Goodhart
Goodhart

9 years ago

On the average, the smaller the battery (if the same chemistry / type) the less power and quicker the discharge rate.

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ΧωρίςΌ
ΧωρίςΌ

Reply 2 years ago

Wow! This is a profoundly wise statement. How did you arrive at such a conclusion?

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mpilchfamily
mpilchfamily

9 years ago

Compair the mAh rating of the batteries. Typically the smaller the battery the lower the mAh it has so it will have less capacity then the larger batteries.

If we are comparing NiCd batteries then the sub C offer about 2000mAh while the AA only offer 700mAh. Now how much fast the AAs will loose there charge compared to the sub C will depend on how many amp the drill draws. But its safe to say the sub C will last more then twice as long as the AA.

I assume you don't live in the USA. Since i'm finding 10 packs of sub C batteries going for about $26. Unless your trying to upgrade the pack to NiMH. In which case you may need to upgrade the charger while your at it.