My toothbrush needs new cells.

[Sinjz]

I finally ripped apart my long dead toothbrush and was able to pull out the battery pack. It's labeled:

Sanyo
Cadnica
3N-600AE
3.6V 600mAh
Ni-Cd

There are three individual cells stacked on top of each other. It seems to be about the same diameter as a CR123 and the length is roughly 3.25 inchs (about two and a half cr123's).

First question is since this is a REALLY OLD Bausch&Lomb Interplak toothbrush, would it make sense to even try to revive it? Are all interplak brush heads compatible? Anybody know? Suggestions to buy a new toothbrush?

Second, can I find some sort of Li-ion battery to use with this? Would it even been a good idea? I have NO idea how the charger actually works. I see no visible metal prongs or anything in the base that the toothbrush is suppose to sit on. It's just a round raise platform. The base of the toothbrush has a round indented hole that goes onto of this. Also, looking inside the base of the toothbrush, there is a bunch of copper wire spun into a circle. Magnetic induction maybe??? If I can use Li-ion, where can I pick one up of the proper size?

Third, if I must stick with Ni-cad, where can I pick up the batter pack or individual cells to use?

Thanks!!!

 

[Don_Redondo]

I'm facing the same decision. I'm on my 3rd Interplak in over 10 years and it's on its way out. I am obviously fond of this brand and would like to keep it running for as long as I can. To answer a few of your questions, there are newer versions available but latest reviews are mixed and sounds like the older ones may have been better. The brushes have changed over the years so you'll have to see if there are any that are still available for your version. Last batch I got was through drugstore.com. They were about $15 for three. In comparison, I recently saw a whole new economy unit at Amazon for around $17. There is also a newer deluxe model that has a separate battery pack that is charged as needed, as opposed to an always on station. It's a better design in theory and may provide longer life. This relates to one of your other questions about changing the cell presumably increasing the capacity of the cells. If you're like most people and return the unit to the charger daily, it's unlikely you're using the full capacity of the cells before recharging anyway. In that case increasing the mAh of the cells would not provide any benefit. One of the things that I have done to keep mine limping along is to unplug the charger from time to time and use the unit until it goes dead – or very low – and then recharge it. It's generally a good idea to discharge NiCds and NiMh cells once in while. And since the life is typically rated in charge cycles, less frequent charging should help. That's why the new design may be a better idea – on paper anyway.

All that said, if you still want to rebuild your current unit here are a few practical considerations.

Can you open it up – sounds like you have – and then close it back up to near original watertight condition? My latest one is the first one where I can open it up in a non-destructive fashion – all the others were glued in a way that the case would have had to be broken to open it and gluing back together would not be pretty. In fact I believe that they are supposed to be sealed and non-user serviceable because they are waterproof electric devices. At least that's what someone told me about an older one that I wanted to fix – he basically said it was sealed for my protection per UL regulations – don't know if it's true but something to think about. It also explains the no prongs - you had the correct deduction that the charge mechanism is induction - so to speak.

Can you find the replacement cells and get them at a reasonable cost? It's been a while since I looked in mine but I believe it has two 3/4AA NiMh cells. At the time I opened it I found a source by searching on-line but it's not very economical buying just a couple less common cells.

Can you replace the cells without damaging the cells or the circuit? In most of these, the batteries are soldered together and the inductive charger has very fine wire that is attached/soldered to the ends of the pack. Soldering cells and fine wire each have their challenges.

I haven't repaired mine but do realize that if I try I may end up killing it in the process. I view this one as a hobby job. If I choose to fix it and it works – great. If it dies and I loose a couple hours and couple bucks – hopefully I'll learn something – and besides it's almost dead anyway so that part is not the issue. If you choose to fix yours, I would try to match the cells as best you can - you definitely don't want to use Li-ions for a number of reasons (voltage, charge cut off, safety, ...) and while ni-mh would probably work there is no advantage for this application. Good luck and let us know how it turns out.

 

[altis]

I would think that redesigning for Li-Ion would be frought with problems. You could possibly use Ni-Mh instead quite easily but watch out for a slightly faster self-discharge and check the charging circuit.

The cells are a size known as 2/3 AF. Check out some of the datasheets here:
http://www.gpbatteries.com.hk/html/techinfo/nimh.asp
http://www.gpbatteries.com.hk/html/techinfo/nicd.asp

By far the easiest solution would be to use a replacement 3N-600AE. They seem to be widely available:
http://www.google.com/search?q=3N-600AE
http://www.cellpacksolutions.com/Search_Data_Sheet.asp?ID=CPS447

 

[Fallingwater]

You can replace the cells, but they need to be NiCD.
I don't know what the specific cells you describe are (they are obviously larger than AAs but smaller than Cs), but if you take a measurement in millimetres it'll tell you the size you need to look for.
Edit: I read your post again and one thing isn't clear: the length you specify (2 1/2 CR123s) is for one cell, or for the entire pack?

Absolutely do NOT replace that pack with a LiIon cell. NiCD chargers can't understand the LiIon chemistry, and your toothbrush might well catch on fire.
NiMH are probably also out of the question, as their charging is more similar to NiCD but still not identical. Put a NiMH in a charger that only understands NiCD and it may well be completely ruined after only a few cycles.

As for whether it's worth to do it... what's gonna cost you more, three NiCD cells or a new toothbrush?

 

[eluminator]

To re-iterate. No, you can't use Li-ion, at least with that charger. Yes you can measure the cells and find replacements on the web. You probably want ones with solder tabs.

You might have luck replacing the Ni-Cads with NiMH. I did that with my Braun-Oral B toothbrush. But I didn't keep it on the charger. I only charged it when the battery got weak.

Actually I found something better. For less than half the price of my Braun with the "non-replaceable" cells and charger, I can get a Braun with replaceable AA cells that uses the same head.

It comes with alkaline cells but now I use NiMH AA cells and re-charge when needed. I think that's about once a month.

 

[PEU]

When I saw this thread I recalled I had to do something about my toothbrush too, so I did this:

Of course, the inductor charger is gone, but I guess runtime will be far superior due to the fact that li-ions almost don't self discharge and a protected 18650 at 2200mAh is more than two times as powerfull as the 950mA provided pack.

For the contacts I used a couple of round pieces I machined in my minilathe, to the bottom one I welded a spring, time will tell if the setup is durable.

Remind me to post an update next month


Pablo

 

[Sinjz]

I have NO idea what the model number for this toothbrush is. It's an older model with a upside down trianglar switch, off-lo-hi (actually O-I-II) Anybody have any idea if they still sell compatible brush heads for this?

I use to put this back on the charger; I think that's what killed it. I will not be doing that anymore. I'll be storing it off charger and only charging it when it's needed.

I dremeled around the center seam where it was sealed shut. It was the only way I could see to get at the insides. I'm surprised I didn't destroy the wires or circuit board inside when I did it. The bottom half of the casing drops off when you either twist that indent out first or when you twist the whole body and the indent pops off. I discovered that by accident. Eveything can easily be put back together, but I will have to find a way to seal it. I 'm not looking for beauty here, so I'll probably just tape it shut. Anybody have a easy, yet more elegant solution? BTW the battery pack to my surprise was NOT soldered it. It drops out the bottom with a little nudging. I got to the battery pack without having to desolder anything. :thumbsup:

Again, it is a 3N-600AE battery pack. I found them online already roughly $20 shipped for one battery pack. BTW, the 3.25" (two and a half cr123) was for the whole pack.

I remeasured and got 27-28mm per cell. Those 23AF cells at 28.5mm look just about right. Could someone just double check that the 'KR600AE' I found are also correct? http://cheapbatterypacks.com/main.asp?sid=783000&pgid=loosecells&chem=NICD

I plan to pick a few of those 'KR600AE' ones up. They come out to a little more than half the price of the 3N-600AE pack.

How about some links to these other toothbrushes?

Lastly, is there some way for me to check if the charger is working before I buy the cells? Where would I put the probes of my multimeter? :thinking:

Nice Peu. He gets to use Li-ions!!! :mecry:

 

[eluminator]

Lastly, is there some way for me to check if the charger is working before I buy the cells? Where would I put the probes of my multimeter? :thinking:

I don't know about your toothbrush but mine made no direct contact with the charger. It's done inductively. There is a coil of wire inside the toothbrush. I suppose that's the secondary of a "transformer" and the primary is in the charger. So you need to put the coil inside the charger and see if you get an ac voltage.

I got rid of that one a few years ago and now I use this one. It works for me and uses the same brush as the old one. I use NiMH AA cells in mine. This one is a lot cheaper and handier.
http://www.dentist.net/oralbbattery.asp

 

[Don_Redondo]

Here are the links to the newer Interplak models.
Economy model: $17 w/free ship if you pad the order to $25 http://www.amazon.com/dp/B000A3ULII/?tag=cpf0b6-20

Deluxe model $34 w/out free ship
http://www.amazon.com/dp/B000FBLBXO/?tag=cpf0b6-20

or this one for around $45 with some extra heads and free shipping– when it's back in stock. (In classic amazon style it was available yesterday but not today. It may come back in a day or two or you could find it at other stores.)

http://www.amazon.com/dp/B000F4Z9NO/?tag=cpf0b6-20

I prefer the Interplak mechanism to the other styles and if you do some digging you will find more people swear by them than at them. One common criticism is that the batteries tend to die after two to three years and no easy way to replace them – as we've been discussing. The deluxe model has a new design that could be better in many ways and could offer the chance to replace the battery pack/charger unit. Unfortunately it hasn't been around long to tell and hoping parts are still around in three years may be wishful thinking. The other issue with Interplak is the design and brand name has been sold to a few different electronic device manufacturers over the last several years (currently owned by Conair) and it hasn't been promoted the way the Sonicare's and Oral B's have. They used to be in most major dept stores but at every switch they have been harder to find – and harder to find replacement heads. There's no telling if it will see a revival or slide into obscurity.

Back to the decision to fix or replace – at twenty bucks for the battery pack with uncertain results, I think I would replace the unit. In my case it's closer to $10 – and I may still just opt for the new one.

 

[DM51]

LOL. When you've fixed up your toothbrush with its new hi-voltage power-pack, all you'll need is some of this_stuff and you'll be away.

 

[GreySave]

<< One common criticism is that the batteries tend to die after two to three years >>


I have the same issue with Sonic Care equipment, which also uses inductive charging. Ours were always off of the charger until they requested a recharge and I think we managed a little over two years (just out of warranty) before the first one failed. I have not yet opened one up so I am not sure what type of cell(s) Sonic Care uses.

 

[hank]

I cracked a Sonicare a while back and it had NiCD AAs, but epoxied into a solid lump. I passed that on to someone from CPF years ago for the parts.

Our second Sonicare, same inductive-charger type, died, wouldn't charge, and went into a drawer for a year -- and when I pulled it out to pass it on I decided what the heck, tried it -- and it charges up fine now. It's been working for months, just as buzzy as when it was new. I have no clue why.

 

[Closet_Flashaholic]

I have been using my 1st Sonicare for about 1.5 years now. I knew they used NiCads, so I ignored the manufacturer's recommendation of always leaving it in the cradle charging. I only charged when needed (avoided the memory effect). Now after 1.5 years, slowly losing capacity, I only get 1 week between charges. I read about the batteries being epoxied, but i think I am going to take a crack at replacing them at some point. $USD100 is just too much money to throw away for 3.00 in batteries. (yeah, I know the heads are $15 ea. but not much I can do about that). There has to be something to dissolve or soften the epoxy (chemical/heat?)..

PS, I was originally an InterPlak user, but the mechanical design of the heads is just too inefficient and the little plastic gears just wear out too fast. The Sonicare is not quite as effective as the InterPlak's are for brushing, but it is close enough...

 

[LuxLuthor]

Yeah, I have to vouch for the Sonic Care Elite which my dentist got a bunch of them to give out free, and if you liked it you bought the base for $40. When I saw their retail prices...this was pretty amazing.

These brushes kick *** in your mouth. So is the battery glued with other parts in the epoxy, or glue affixed to the inside of the handle? Cause if I can throw out the batteries and save the electronics that would be sweet, and I'll glue back the bottom and dip it in some liquid grip to seal it.

 

[altis]

Batteries not included:

 

[BIGIRON]

Have used the OralB's for years and get several years from each. One thing to watch for, when you think they're not performing 100%, is a buildup of crud where the shaft comes thrugh the housing. A cleanup and drop of light oil often gives better performance. I've also found that if I remove the brush and rinse the shaft every couple of uses, the problem never occurs (and leave the brush off the unit til' it dries).

 

[wjb3]

Acording to the phone customer service, the Sonicare Xtreme E3000 Power Toothbrush should take eneloops (
http://www.target.com/gp/detail.htm...9/601-8983664-6580127?ie=UTF8&asin=B000FEIOHW ). My local Target & RiteAid carry them. When my current Sonicare dies (had it for 5 years), I will try one.

-wjb

 

[pae77]

I just started using a Sonicare Elite (got two handles, 3 brush heads, etc. at Costco the other day for $99 w. coupon). My first electric toothbrush. Teeth feel very clean after using it. Very happy with that aspect. Planning on only charging it when the batteries are almost completely discharged.

Was very disappointed though to discover the device uses non user replaceable (at least not easily) NiCd instead of easily replaceable NiMh and the charger doesn't accept international voltage. Pretty shameful in this day and age. I guess they really want to force you to buy a new one when the batteries wear out. Still the device is otherwise so good I probably will just
end up replacing handles every two years or so whenever the NiCds eventually wear out.

 

[Sinjz]

I see toothbrush suggestions ranging from $15 to $100. I wonder how they all compare. I believe mine was an $80 unit (I think from BJ's) seven years or so ago. Would I be better off going with some $20-30 model today or picking up that $20 battery?

The Sonicare Elite looks good which model do you guys have? Any online deals?

 

[Sinjz]

BTW, I recently picked up a battery powered Colgates kids toothbrush. I don't think it does anything!!! Nothing is rotating. It just vibrates a little. Is that really helping that much?