2807
« on: August 26, 2010, 08:52:17 AM »
Hello list I have various bosch 24 volt cordless power tools which all use the same batteries. Recently 3 of the batteries have failed & I have sent them away to have them re-celled. What should I be doing in order to preserve their lifespan? Discharging completely each use or only discharging to a certain percentage - say 50%. 2807
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EccentricAnomaly
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« Reply #1 on: August 26, 2010, 09:20:56 AM »
These are NiMh presumably? Discharging individual cells may or may not be a good idea: it depends on the technology and opinions differ anyway. Fully discharging batteries (i.e., strings of multiple cells) is almost always a bad idea. Different cells, even from the same batch, will have slightly different characteristics so a few will become discharged before the rest and will consequently be reverse charged as the last dregs flow from the stronger cells. This is typically not good and will make the problem worse next time round.
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Justme
« Reply #2 on: August 26, 2010, 10:15:42 AM »
I have just had a 24v tool battery fail on me during heavy use. On stripping it the interconnects between the cells had rusted away. So I would say keep the battery in the dry. Oh & so that I dont have to buy a new one what I have done is to wire up two car bats to 24v & fit a heavy cable to the broken drill battery so I now can use one of the original two bats as normal & when thats charging or I am doing lots in one area I can use the car bat 24v "pack" to power the drill.
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Navitron solar thermal system 30 x 58mm panel 259L TS 1200watts solar 120vdc FX80 Solar controller Victron 12v 3000w 120a 6kva genny 6 x 2v cells 1550amp/h 5C 24 x 2v cells 700amp/h 5C Total bank 4350 amp/h 5C
Billy
Guest
« Reply #3 on: August 26, 2010, 10:33:39 AM »
2807
I have always numbered my batteries and used them in strict rotation. I do flatten my nicads and recharge to avoid memory effect. My wet nicads are also subjected to the same treatment by flattening with a load and then shorting out the individual cells, then recharge and even an electrolyte change. Perhaps not on the drill battery though. The bringing back to life by flashing across an arc/mig welder is something I will try but haven't had a dead one yet, well not since I found out about it anyway.
I do take EAs point about strings of cells mind and I thinks that is what the clip is supposed to sort out.
Billy
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roscoe
« Reply #4 on: August 26, 2010, 11:45:32 AM »
Battery tech - you get what you pay for ..... I have a pristine Makita drill and 3 aged batteries NiMH/NiCad can't remember. It is 5 years old paid its way, but for last 2 years it drives me nuts as the batteries discharge if not used for a couple a days. Reluctantly, I finally gave in (costly L-ion upgrade) and am delighted to say I no longer start jobs in a fowl mood. Same for a L-ion Bosch hedge trimmer AHS-52 best tool in the garage, a perfect marvel.
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davebodger
« Reply #5 on: August 26, 2010, 11:55:22 AM »
I have a Ryobi One+ system with lots of tools and 4 Nicad battery packs which I have numbered so I can track them.
The battery packs are about 6 years old now and I have tried to use them in sequence although this is never perfect.
One died last year and refused to revive despite all my efforts (similar to those quoted above).
The other three are in various stages of degradation although one performs almost like new.
My feel is that the one that has lasted best is the one I have "worked" hardest.
The one that has spent the most of it's life in "reserve" is now the one with the lowest usable capacity.
So I think it's a case of use it or loose it
Interestingly I have now bought a new Lithium-Ion battery which came with a new "Smart" charger (capable of recharging all One+ batteries of any type) which has now recharged the Nicad packs to the highest voltage I have seen them at for a long time. I've yet to use them in anger on a job but here's hoping.
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Soladin Grid-Tie 400Wp tracker in London NW5.
Amy
« Reply #6 on: August 26, 2010, 03:19:31 PM »
My Ryobi plus one batts have all but died a death and wont hold a charge overnight even So, Dave, which smart charger is that and where do i get one? Will it resurect my batts or do I need new ones? Will the new lithium batts work in my old blue and yellow tools?
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Billy
Guest
« Reply #7 on: August 26, 2010, 04:30:12 PM »
I tried Wicks, Ryobi blah blah.
I don't think they are good for serious work, Makita all the way home for me.
Billy
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Amy
« Reply #8 on: August 26, 2010, 05:11:15 PM »
When your jobbing on a site full of ejits, Makita is an expensive tool to have stolen. My Ryobis have done me 4 yrs, so owe me nothing now.
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Billy
Guest
« Reply #9 on: August 26, 2010, 06:17:52 PM »
Ames,
yer have done well I think, sadly my Ryobis only lasted a few months of abuse.
Any more newz on the ship?
It did seem to be coming along rather nicely, and mine was a lot lot lot slower.
Billy
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Amy
« Reply #10 on: August 26, 2010, 06:41:32 PM »
My 18v circisaurus was the first casualty but it was doing sterling service cutting concrete roof tiles at the time. Then the jiggasaurus died when the blade clamp became extinct. The angle drill doesnt get used much but its got enormouse torque The drill no longer has reverse thanks to fat boy slim shifting gears when still in motion But the 24v SDS is still demolishing everything in its path Go see the blog Billy, baby is due this weekend. Its all happened a bit premature like. Shall I think of a popular county themed name for her?
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tony.
Guest
« Reply #11 on: August 26, 2010, 09:31:18 PM »
bosch 24volt sds drill purchased 1998 still going strong, existing battery and charger. dewalt 14.4volt drill driver 2000- 2 batteries one fine one lasts 10 minutes. as other posters have said when you have multiple batteries you need to rotate the batteries. discharge fully and recharge. of course this was all before l-ion batteries came along. tony
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rogeriko
« Reply #12 on: August 26, 2010, 09:56:28 PM »
My 2 power drills from B&Q died after about a week, maybe because they were only 6 pounds each on sale, but guess what, these 12 volt batteries fitted perfectly in the battery base. now I have 2 extremely powerful very long lasting drills that even charge on the original base!!
Amy
« Reply #13 on: August 26, 2010, 10:36:49 PM »
Maybe I should take one of my casings apart and see what I can get to retro fit back in
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rogeriko
« Reply #14 on: August 26, 2010, 10:40:43 PM »
12 volts Length:3.82", Width:1.69", Height 2.05 I use them daily and only seem to charge them monthly theres plenty on ebay small batteries different sizes
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