Jump to content

"Re-celling" rechargeable batteries


Alan Zoff
 Share

Recommended Posts

With Spring around the corner, I'm getting ready for the next batch of home improvements chez nous.

In a moment of weakness (an expensive Bosch drill having "walked"), I bought a Silverline 24V cordless drill a couple of years ago for what seemed a bargain price. The drill itself seems OK but the batteries (2 were supplied and both as bad as each other) drain very quickly, and it just doesn't have anything like the drilling power of other makes. In fact, it's almost useless. So I went back to using an old B&D corded drill.

While surfing recently for a possible replacement cordless drill, I read that Silverline use very cheap Chinese batteries that are known for their poor performance and are best avoided. However, one anonymous commentator intriguingly added "unless you re-cell them". Does anyone know if that is feasible or cost-effective? If not, the Silverline will probably be heading for the dechetterie.
Link to comment
Share on other sites

Perfectly feasible if the battery packs are held together with screws, even those that are friction welded can be split apart with care, you need a powerfull soldering iron and a supply of tagged nicad cells, its been 8 years since I did any so dont know what they cost now but they were less than £2 per cell, I used to buy them from CPC but Farnell, RS or Maplins are also good sources.

There is a guy not far from me in St Quentin that does this for a sideline although he is very expensive, for my Dewalt its cheaper to buy a new battery pack, he did one for a friends American nail gun and I peeked inside and saw that his batteries come from the UK which indicates that is the place to source them.

Link to comment
Share on other sites

Many thanks Chancer.

That gave me the confidence to open one of the battery packs. Not sure what I was expecting to find inside but was a little surprised to see as many as 18 1.2v NiCd 1500 mAh cells. And quite ropey and rust-tarnished they look, too.

So that would be 36 cells needed for the 2 packs, a total of £72, at £2 a cell (you were right again about the price from a quick search on the net).

The Makita drill kit on offer at just over £100 is starting to look good value, and is of course the sort of thing I should have bought in the first place.
Link to comment
Share on other sites

Well I was also searching at the same time.

Buying direct from Hong kong via ebay seems the cheapest, between £4 and £5 for 4 cells including free delivery according to the capacity, the prices I mention are for 2000-2900 mAH.

I bought a few of the Makitas when they were £72 with the discount from Screwfix, I sold 2 and kept one, it has proved to be really good, however I have been using my pair of Elu combi drills for 15+ years now and am so attached to them that I think that I will re-cell all 4 batteries, they are only 14.4volt but pack the same punch as the 18v Makitas and weigh about the same.

They are my standby drills now, one in the UK the other in France as a back up to the Makita but if it were re-celled I think the Makita would become the back up drill.

Link to comment
Share on other sites

It's rarely cost effective to replace cells like that but in certain circumstances it can make sense.

As Chancer suggests the voltage thing is a bit of a marketing con as most lay people equate volts with power which is far too simplistic and when it comes to cordless tools it's very much a question of getting what you pay for so if you want a quality tool which is going to last buy a branded make and the best one you can afford, Li-Ion batteries are to be preferred.

Link to comment
Share on other sites

[quote user="AnOther"]it's very much a question of getting what you pay for so if you want a quality tool which is going to last buy a branded make and the best one you can afford, Li-Ion batteries are to be preferred.

[/quote]

Absolutely. The most common battery drill and screwdriver used by the trades is the Makita, they last for years and the batteries are easy to get hold of all over the world but they are not cheap (around £200). If you need bigger and SDS then buy Bosche professional ones (they are normally blue in colour) again very expensive (£400 ish) but they will last for years and you can still get batteries for even the very old ones.

Link to comment
Share on other sites

[quote user="Quillan"]

[quote user="AnOther"]it's very much a question of getting what you pay for so if you want a quality tool which is going to last buy a branded make and the best one you can afford, Li-Ion batteries are to be preferred.

[/quote]

Absolutely. The most common battery drill and screwdriver used by the trades is the Makita, they last for years and the batteries are easy to get hold of all over the world but they are not cheap (around £200). If you need bigger and SDS then buy Bosche professional ones (they are normally blue in colour) again very expensive (£400 ish) but they will last for years and you can still get batteries for even the very old ones.

[/quote]

I think you'll find it's pronounced Maki-a in the building trade [;-)]  These tools have no battery overload protection so regularly burn out and batteries die.

Bosch have protection but it requires you to un clip the battery and re install before the tool works again which is a pain if you are holding the work in position with one hand and the drill bit snaggs. 

Dewalt (battery protection) are popular except with users who have just found out the new Li on batteries don't fit the older versions.

Metabo (battery protection) have the 4A/h battery which provides more work time and has a 3 year guarantee on the tool and batteries.

All of these are incredible compared to domestic cordless tools and as the manager of a high street builders merchant said "never buy a Silverline tool with a motor" after a wall chaser I bought burned out after 7 feet of chasing [:)]

Link to comment
Share on other sites

Good to know as I have nothing but praise for Silverline non powered tools.

Are the Hong kong ebay cells likely to be pants like the ones in the Silverline tools?

Where can I find decent ones like used in the Bosch and Dewalt battery packs which are also made in China?

I used to buy a good brand, think it was Varta but that doesnt count for a lot these days, its 48 cells so I dont want to get it wrong.

Link to comment
Share on other sites

[quote user="Théière"][quote user="Quillan"]

[quote user="AnOther"]it's very much a question of getting what you pay for so if you want a quality tool which is going to last buy a branded make and the best one you can afford, Li-Ion batteries are to be preferred.

[/quote]

Absolutely. The most common battery drill and screwdriver used by the trades is the Makita, they last for years and the batteries are easy to get hold of all over the world but they are not cheap (around £200). If you need bigger and SDS then buy Bosch professional ones (they are normally blue in colour) again very expensive (£400 ish) but they will last for years and you can still get batteries for even the very old ones.

[/quote]

I think you'll find it's pronounced Maki-a in the building trade [;-)]  These tools have no battery overload protection so regularly burn out and batteries die.

Bosch have protection but it requires you to un clip the battery and re install before the tool works again which is a pain if you are holding the work in position with one hand and the drill bit snaggs.  [/quote]

Well it's spelt Makita which is how I have always heard them pronounced. I have one of the earlier ones which take the long battery, works as good as the day I bought it on the recommendation of a guy who built office partitions. I have had one new battery for it over the years and it has been well abused. I had a Bosch but it never got the use so I sold it on. The guy who has it is a family friend and it still works fine. When I designed computer rooms all the trades had either Makita or Bosch drills and they were all battery models. The Bosch seemed quite happy drilling straight through 8" x 4" metal trunking in to pre stressed concrete. If it was good enough for them then it was good enough for me and time has proved me right.

I also have two Black and Decker battery drills that came in a kit with sander, jigsaw and chuck attachments. They must be 20 years old now and have had both their batteries replaced a couple of years ago, they still work well. I was quite supprised you could still buy original batteries for them.

Link to comment
Share on other sites

Chancer the best cells are made by Panasonic, they lead the world on battery technology of this type.

Q, my very first cordless drill was a B&D and it's still going on the original battery which is 20+ years ago, more of a screw driver really.  Yes I think the long battery Makita's were better than the latest, yes the latest have the power but in turn that can fry the motor in 1/2 second. The older Bosch again aren't bad but if someone was buying new they would probably be getting a Li on so we have a different beasty to think about. Nothing wrong with the Bosch, powerful and capable but if you stall it, say breaking through your metal trunking then you must remove the battery and then re insert it when others you just re apply the trigger.  The Milwaukee range are the most powerful Li on versions of the AEG which is the same company as Ryobi.

I went for Metabo for the extra run time and 3 year warranty, lets see if they (or I) am still going in 20 years [:)]

Link to comment
Share on other sites

As is invariably the case, you guys know more about this sort of stuff than I do. But it's nice to learn.

I also hit on this video which might be of interest, if perhaps a bit basic for some of you:

http://www.youtube.com/watch?v=1e8hHLyXAyQ

(Looks like you will have to copy and paste to browser as I have forgotten how to turn it into a direct link)

Link to comment
Share on other sites

Sorry if this is a dim question. But if I buy 18 of the replacement tabbed cells (on Ebay for about £20 inc postage) and solder these together in place of the existing Silverlines, will they charge the same in the Silverline charger, given that the originals are 1500 mAh and the new ones are 2500?

I'm willing to give it a go with one of the batteries for 20 quid, but not much point if the charger will no longer be suitable.
Link to comment
Share on other sites

I think so as the charger just gets the batteries up to a certain voltage, it will just take longer.

My Elu (Dewalt) charger was marked 1.3 or 1.7ah as that was all was available at the time, I now have 2ah battery packs and they charge all right, I was surfing Ebay again at the same time as you and think I will go for 2.5ah this time.

This seller seems cheap and with the most options:

http://www.ebay.co.uk/itm/400422467659?ssPageName=STRK:MEWAX:IT&_trksid=p3984.m1423.l2648

Or this one:

http://www.ebay.co.uk/itm/380578982091?ssPageName=STRK:MEWAX:IT&_trksid=p3984.m1423.l2649

Link to comment
Share on other sites

If I do recell all 4 of the batteries then I am going to make up an adaptor from an old drill body to discharge them through a headlamp bulb or something similar and will get into the habit of doing all my batteries every couple of months.

Time will tell if its worthwhile, I never had a battery failure when my drills were used every day until I took my first holiday in 2 years, it was a month and they were foutu afterwards, the ones in my UK drill regularly get left for 1-2 months, I will definitely discharge them each time now, I tried this time while I was defrosting the fridge etc but it takes hours via the drill motor off load and doesnt do the drill any good so I must make up something.

Link to comment
Share on other sites

[quote user="Alan Zoff"]will they charge the same in the Silverline charger, given that the originals are 1500 mAh and the new ones are 2500?[/quote]Yes, charging is sensed by voltage and towards the end by temperature so as Chancer says it will work but just take longer.

Link to comment
Share on other sites

Sometimes with the battery packs it's just one or two cells that go down but that effects the whole pack. On my Li Po batteries My balance charger has additional leads so can tell which cells is duff and monitor the full charge/discharge. Too advanced for the average builder and is Maki-a but only a matter of time till they idiot proof it........until nature provides a better idiot [:)]
Link to comment
Share on other sites

Yes, way back when I re-celled batteries for others, friends etc not as a business, I would only replace the cells that had failed, the others were fine.

With that in mind I might try kick-starting my battery packs with my handbag welder.

In fact once charged a few times they all perform quite well its just they self discharge relatively quickly, if I use them every day its not a problem.

The reason I use a 2nd spare battery drill here in France is partially laziness/convenience, my work is spread across 4 floors and also because when I used one drill I dropped it off the scaffolding and was really stuck, it looked like Frankenstein by the time I had resurrected it. I suppose now that Screwfix deliver its not such an issue.

Link to comment
Share on other sites

I have ordered the 20 pack from Ebay, having since realised that there are a further 2 cells in the neck of the battery pack. I should have worked out before that 20 would be needed at 1.2 each to give 24 volts....  Not exactly rocket science!

The Ebay picture seems to suggest that the tags simply push into each other, but that might be wishful thinking on my part, not having used tagged batteries before.

Bit of a wait before the cells arrive from Hong Kong but I will post the result. I just hope the Silverline motor is efficient enough to justify replacing the cells, but there is no doubt that original pack is of very poor quality.

I was interested in the comment that Silverline hand tools are of better quality. I read recently that someone considered their spanners to be dangerous as the jaws on one he had bought had spread apart or broken under only moderate force. I think there might be a picture somewhere which I will try to find.

Link to comment
Share on other sites

Re the battery in the neck, been there got the T shirt etc.

The tags need to be soldered together, you will need a very substantial iron, the old solid copper type that you heat with a flame is the best for the job.

The silverline tools that I have tend to be builders tools, hammers, cold chisels etc, actually I think that my pipe bender that bent its arms instead of the pipe might be silverline!!!

Link to comment
Share on other sites

Thanks for the heads-up on the soldering Chancer.

I can't find the spanner picture I was looking for but found this comment on a forum:

"Silverline tools are great, they come with a "Lifetime Guarantee" - so as long as your supplier is just down the road you can replace them every time you use them, this being essential as they break when you remove them from the packaging."

Probably slight exaggeration there, and of course you shouldn't believe everything you read on a forum!
Link to comment
Share on other sites

  • 3 weeks later...
I would not be too sure that there will be enough room to solder the cells together.I chose a different route when three of my cordless drills started suffering with duff batteries, I replaced the NiCd or NiMh cells with a LiPo pack of equivalent (or very close) voltage, just opened the plastic battery holders, cut out the old cells, retain the connector, and purchase the biggest capacity LiPo pack that will fit in the available space, check out hobbyking (for example) for masses of modellers packs. You will need a new charger, you can get good series chargers now for LiPo packs quite cheaply that balance charge through the series connector, so just make a small hole in the battery casing and leave the series connector outside the pack. The only drawback is that, in use, the drill will not shut off before the pack is exhausted, and that will be detrimental to the battery so at the first sign of the drill slowing down I put the pack on charge. New life for old power tools....
Link to comment
Share on other sites

The battery driven tools that the DIY stores in the UK display in the stores are smashed beyond repair and binned each time the display is changed because its policy not to sell ex display items, even to staff. ( Same applies with corded tools ) The suppliers often give them FOC

The batteries however, because they are not handled by Joe Public, are kept by the store. Some go to customers with warranty claims

If you need a replacement battery it's worth asking in store if they have any "put away" even for a model a couple of years out of date

I ended up with 2 spare batteries for a Bosch drill at a pound each just by asking ( they have no barcode, so no fixed price )

John

Link to comment
Share on other sites

  • 1 month later...
Finally got round to rebuilding the battery pack today. Fiddly job - would never have managed it without the pretinned tabs.

It's important to keep any bare tabs clear of one another until soldered. I gaily starting pulling off the insulation before I realised how easy it is to short the cells - with quite dramatic results. Burnt the top off one cell and made a nice hole in the wooden board I was working on. Fortunately, a few of the original cells looked perfect so I was able to reuse what looked to be the best of those to replace the ruined new one.

I will be interested to see now how the performance of the drill compares with original pack. It worked straightaway but I need to give it a full charge before giving it a proper trial.
Link to comment
Share on other sites

I always used Makita when on my tools however when my Makit batteries got tired for my drill driver about 8 years ago I bought a stop gap 'Erbauer' 14.4 volt drill from screwfix I think. It has done a sheldload of work and is as good as new ...batteries both hold a good charge and the unit feels as torquey as my 18v Dewalt. As a good budget range of tools Erbauer gets my vote.

 

Link to comment
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
 Share

×
×
  • Create New...