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18 Volt Lithium-Ion Batteries - Ah rating situation

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  • #46
    Re: 18 Volt Lithium-Ion Batteries - Ah rating situation

    Originally posted by undertheradar View Post
    Could it be that Craftsman went to someone else for the new battery/charger, but the tools are still made by TTI?
    Sure seems unlikely...unless they are outsourcing the electronics. Do you know who makes the battery cells inside the Craftsman. I always assumed they were the same as Ridgid, minus one cell...since the tool was also made by TTI.

    I stumbled on a guide, it is on the net somewhere, that referenced who was the actual manufacturer of a Sears item by the part number. Can't find it now, and, if I recall it changed over the years and wasn't up to date but if you find it, it might help.

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    • #47
      Re: 18 Volt Lithium-Ion Batteries - Ah rating situation

      Originally posted by Disaster View Post
      Do you know who makes the battery cells inside the Craftsman.
      Sanyo.

      Comment


      • #48
        Re: 18 Volt Lithium-Ion Batteries - Ah rating situation

        Undertheradar - I've talked about this on here before, but the thing that happens with the 36V saw is that they impose a current limit on the battery. Essentially what happens is that under high overload situations, the battery monitors what's going and and prevents situations where high heat could damage the motor or cells due to extreme current. It's NOT anything to do with alleged high "sag" of A123's cells as you call it.

        One problem I've found with the saw is that the blade guard is the biggest piece of crap I've ever experienced, but I've learned to work around it. It tends to stick on everything and can actually cause the saw to twist into the kerf, causing unnecessary strain on the motor. They really need to make a better blade guard.

        Originally posted by undertheradar View Post
        where it notes: "Even though it could cut super fast, its 7 1/4-inch blade didn't leave much reserve torque, the saw stalled fairly easily at times, and the battery had a short life." Stalling easily means poor power in my mind.

        Comment


        • #49
          Re: 18 Volt Lithium-Ion Batteries - Ah rating situation

          Originally posted by Sceeter W Wheels View Post
          Undertheradar - I've talked about this on here before, but the thing that happens with the 36V saw is that they impose a current limit on the battery. Essentially what happens is that under high overload situations, the battery monitors what's going and and prevents situations where high heat could damage the motor or cells due to extreme current. It's NOT anything to do with alleged high "sag" of A123's cells as you call it.

          One problem I've found with the saw is that the blade guard is the biggest piece of crap I've ever experienced, but I've learned to work around it. It tends to stick on everything and can actually cause the saw to twist into the kerf, causing unnecessary strain on the motor. They really need to make a better blade guard.

          I'll sort of buy that and sort of not. Granted, totally agree that they limit the current on the Dewalt, especially as they have to: they use 16 gauge wire for the main wires from the cells! Thinnest wires I've every seen coming off a battery pack. Still, if you look at some of A123's own data, or even the data on the Moli-cells above, they show (granted, on constant current plots), that the Ah/capacity varies negligibly from the low current number. But the voltage sags SEVERELY from that at lower current.

          Perhaps you're correct in that it's the current limit in this battery that causes the saw to bind/stall more than the Bosch or the Hilti (**the latter of which I personally haven't tested; going by the review here). Regardless, the voltage sag does happen, rather severely in these cells at higher currents, per A123's own data.

          I've instrumented a Dewalt pack and used that instrumented pack to do drilling and other tasks. A123 has claimed (see IEEE link above) that their batteries deliver 130Wh/kg in the tools. Drilling 1" holes in thick samples, the pack ACTUALLY delivers a tad under 25Wh/kg (yes, cell weight only). That's a severe difference in delivered energy between the nominal load energy (allegedly 130Wh/kg) and the actual delivered. The Ah comes out pretty similar, it's the voltage sag that explains the difference. Wh = Ah x V. If the Ah are nearly the same, and the Wh drops precipitously... that is voltage sag.
          Last edited by undertheradar; 10-26-2007, 11:28 AM.

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          • #50
            Re: 18 Volt Lithium-Ion Batteries - Ah rating situation

            Originally posted by Sceeter W Wheels View Post
            with the 36V saw is that they impose a current limit on the battery. Essentially what happens is that under high overload situations, the battery monitors what's going and and prevents situations where high heat could damage the motor or cells due to extreme current. It's NOT anything to do with alleged high "sag" of A123's cells as you call it.
            The A123 cells, can handle very high currents (vs. competitors Lithium Ion batteries) so it is more likely that they would limit current to protect the rest of the circuitry and motor. Power is voltage times current and to get the same power these lower voltage DC motors need to draw a lot more current than 110 volt AC motors do.

            It is also possible that the voltage sag is confusing the electronics and causing them to switch off (to protect the battery.)

            It would be hard to tell without removing the electronic circuit and testing it with various voltages and currents.

            Comment


            • #51
              Re: 18 Volt Lithium-Ion Batteries - Ah rating situation

              So, have you used the DeWalt 36V circ saw?

              Originally posted by undertheradar View Post
              I'll sort of buy that and sort of not. Granted, totally agree that they limit the current on the Dewalt, especially as they have to: they use 16 gauge wire for the main wires from the cells! Thinnest wires I've every seen coming off a battery pack. Still, if you look at some of A123's own data, or even the data on the Moli-cells above, they show (granted, on constant current plots), that the Ah/capacity varies negligibly from the low current number. But the voltage sags SEVERELY from that at lower current.

              Perhaps you're correct in that it's the current limit in this battery that causes the saw to bind/stall more than the Bosch or the Hilti (**the latter of which I personally haven't tested; going by the review here). Regardless, the voltage sag does happen, rather severely in these cells at higher currents, per A123's own data.

              I've instrumented a Dewalt pack and used that instrumented pack to do drilling and other tasks. A123 has claimed (see IEEE link above) that their batteries deliver 130Wh/kg in the tools. Drilling 1" holes in thick samples, the pack ACTUALLY delivers a tad under 25Wh/kg (yes, cell weight only). That's a severe difference in delivered energy between the nominal load energy (allegedly 130Wh/kg) and the actual delivered. The Ah comes out pretty similar, it's the voltage sag that explains the difference. Wh = Ah x V. If the Ah are nearly the same, and the Wh drops precipitously... that is voltage sag.

              Comment


              • #52
                Re: 18 Volt Lithium-Ion Batteries - Ah rating situation

                Anything's possible, but I don't think it's an unintentional mistake or anything to do with voltage "sag" accidentally triggering anything. If it were a design mistake (or if this were seriously a user issue) it would probably be be "corrected" by now.

                But as I said earlier, I don't really find that there's a major blade bind or power issue to begin with, at least nothing near the extent that they seem to indicate in this review where it's the first thing out of the gate and makes it sound like the saw is useless. I don't know, maybe it's the blades I use are very good, or I just happen to have a so-called golden unit. But then again if this circular saw were wimpy and lacking in power in a really bad way, then the REAL consumer reviews on Amazon (let's use them as an example) would be extremely negative, which they are not. Most feedback I've seen so far on it is very positive.

                Originally posted by Disaster View Post
                The A123 cells, can handle very high currents (vs. competitors Lithium Ion batteries) so it is more likely that they would limit current to protect the rest of the circuitry and motor. Power is voltage times current and to get the same power these lower voltage DC motors need to draw a lot more current than 110 volt AC motors do.

                It is also possible that the voltage sag is confusing the electronics and causing them to switch off (to protect the battery.)

                It would be hard to tell without removing the electronic circuit and testing it with various voltages and currents.

                Comment


                • #53
                  Re: 18 Volt Lithium-Ion Batteries - Ah rating situation

                  Originally posted by undertheradar View Post
                  I'll sort of buy that and sort of not. Granted, totally agree that they limit the current on the Dewalt, especially as they have to: they use 16 gauge wire for the main wires from the cells! Thinnest wires I've every seen coming off a battery pack.
                  I too was amazed how how tiny the wires were in tool battery packs considering that people lean toward 14 or 12...sometimes even 10 gauge wiring in RC's and tools have much bigger motors. When you say 16 gauge was the thinnest you've seen, are you just talking the Lithium packs because I thought I recalled the wiring in Ryobi's NiCad packs (and Sears C3) being even smaller...like 18 or 20.

                  I suspect, based on battery drain times, even with big motors tools, tools don't draw the currents we see in RC....at least not for the sustained per periods. Also, RC racers are much more concerned with getting the last .001% of efficiency out of their powertrains. They want the lower resistance of the larger wire.

                  Here is an interesting chart with recommended wire sizes.

                  http://www.powerstream.com/Wire_Size.htm

                  I don't understand the "power transmission" recommendation....perhaps that assumes continuous draw at that current and it is designed to stay cool. That would explain the hugely conservative number.

                  Comment


                  • #54
                    Re: 18 Volt Lithium-Ion Batteries - Ah rating situation

                    Just did a quick calculation using their calculator at the bottom of the page. At 30 amps, assuming about 1 foot of total wiring, and the voltages we are talking about you get about a .25 volt drop. If you switch to 12 gauge that drops to .098. That is about 8 watts of wasted power or 25 btu's of generated heat for 16 gauge wiring vs. 3 watts wasted or 9 btu's of heat for 12 gauge. If you push it to 100 amps you get 83 watts vs. 33.

                    Comment


                    • #55
                      Re: 18 Volt Lithium-Ion Batteries - Ah rating situation

                      Originally posted by Disaster View Post
                      I stumbled on a guide, it is on the net somewhere, that referenced who was the actual manufacturer of a Sears item by the part number. Can't find it now, and, if I recall it changed over the years and wasn't up to date but if you find it, it might help.
                      Found the guide while looking for something else.

                      http://www.professional-power-tool-g...ource-Code.htm

                      001 Stevens
                      002 Lemont Industries
                      071 Agri-Fab Corp
                      093 Ametek
                      002 Lemont Industries
                      101 Atlas Press Co.
                      102 Walker Turner
                      103 Sarlo Power Mower Inc.
                      106 Whirlpool
                      108 Covel Mfg. Co.
                      109 AA Engineering
                      110 Whirlpool
                      111 Watson Mfg Co.
                      112 Parks Tool Co. (Woodworking equipment)
                      113 Emerson Electric Co.
                      114 Pioneer Gen-E-Motor
                      115 Rixon
                      116 Matsushita
                      119 Frigidaire
                      121 Dille & McGuire
                      122 Blair Mfg.
                      123 Yard-Man
                      128 E.T. Rugg
                      129 Mono Mfg. Co
                      131 Rally/Roper Lawn (American Yard Prod.)
                      133 American Yard Products
                      135 Skil/Bosch
                      136 Toro Mfg. Co
                      137 Rexon
                      139 Chamberlain
                      143 Tecumseh (Lauson Power Prod. Co.)
                      144 Trane
                      145 Country Manufacturing
                      147 Village Blacksmith (Div. of McGraw Edison)
                      149 Amt
                      150 White Consolidated
                      153 State Industries
                      155 Preway
                      160 Wisconsin Magneto
                      161 Nakajima
                      171 Vermont American
                      174 Caloric
                      175 Bissell
                      176 Murata
                      180 Lambert Corp.
                      187 White Consolidated
                      190 Pioneer
                      198 Whirlpool
                      202 Gannon Mfg. Co.
                      204 Iona
                      214 Bissell
                      216 Phonemate
                      217 Eska Outboards
                      219 MTD
                      222 Panasonic Video/Audio
                      225 Outboard by Chrysler/Force
                      233 Broan
                      234 Beard-Poulon & Lazy Boy
                      235 Ingersoll Rand
                      241 Fimco
                      247 MTD-Modern Tool and Die (not MID)
                      250 J.I. Case
                      253 Gibson (now Frigidare)
                      256 Emerson Electric
                      257 Allegretti & Co. & Paramount
                      264 Emerson Electric
                      268 Brother International
                      271 Kioritz Corp. - Echo
                      274 RCA
                      278 GE
                      281 Electro-Aire
                      283 Thomas Industries
                      289 Sharp
                      291 American Lawn Mower
                      292 Lennox
                      294 Tunturi
                      302 IBM
                      304 Funai
                      306 Belsaw
                      312 GTE
                      315 Ryan
                      316 Ryobi
                      317 Makita
                      319 Hand Tools International
                      329 Inventa
                      330 Apple
                      328 McLane
                      329 Ametek
                      334 Commodore
                      335 Amana
                      336 Electrolux
                      340 Necchi
                      342 York
                      351 Colovos Co.
                      253 White Consolidated
                      355 Roper Outdoor
                      358 Beaird - Poulan, Inc.
                      359 Bolens Products Div.
                      362 General Electric
                      363 General Electric
                      365 US Lawn
                      366 Koss Eletronics
                      367 AT&T
                      372 Zeus Generator Co.
                      374 Diversified Products
                      378 Omark (Oregon)
                      380 Moto-Mower, Inc./Subsidiary of Dura Corp.
                      385 Jamac
                      387 White Rodgers
                      390 King-O-Lawn
                      401 Bissell
                      410 John Bean Food Mach. & Chem.
                      415 Char Broil
                      417 Stover Engine Works
                      426 Parker Sweeper
                      445 Melmer
                      452 AT&T
                      457 Code-A-Phone
                      459 Technics
                      464 GE
                      471 Bionaire
                      472 Dremel
                      473 Quincy Compressor
                      474 Sony
                      476 Coleman
                      480 Bose
                      484 Airtemp
                      486 Agri-Fab
                      490 Indiana Steel
                      498 Didier Mfg. Co.
                      500 Briggs & Stratton Corp.
                      502 Murray Ohio
                      509 Payne
                      517 Homelite/Jacobsen
                      521 E Z Rake Co.
                      523 MGM Technology
                      534 Clausing Lathe (Former Atlas Press Co.)
                      536 Western Tool & Stamping (Before AMF Lawn & Garden Div.)
                      538 AMF and or Murray
                      549 Midwest Ind
                      552 Cobra
                      562 Toshiba
                      564 Sanyo
                      565 Sanyo
                      566 Packard Bell
                      568 Panasonic
                      572 Dremel
                      575 Sharp
                      576 D & M (now Frigidaire)
                      580 Generac Corporation
                      582 Clinton Engine Co.
                      583 Remington/Desa
                      586 Panasonic Office Equip.
                      587 White Consolidated
                      596 Amana
                      604 Digital Equipment Co.
                      610 Ohio Steel Fabrication
                      613 Consolidated Technologies
                      619 Arps Corp.
                      620 Enviro-Research
                      621 Bryant
                      622 Kelvinator
                      625 Ecodyne
                      626 Magnavox (Philips)
                      628 White Consolidated
                      629 Jenn-Air
                      636 Echo
                      639 King-O-Lawn
                      640 Cerwin Vega
                      647 Roper
                      651 O.M.C. Dist. (also Standard Eng.)
                      654 Mott
                      663 Air Cap Industries
                      665 Whirlpool
                      666 Kitchenaid
                      668 Echowater
                      678 Vac Appliances, LTD
                      680 Generac
                      683 Philco (Italy)
                      704 Royal
                      705 Canon
                      716 H.H.Scott/Emerson
                      719 Tappan
                      721 LG Electronics
                      723 Yamaha
                      733 Fairbanks Morse
                      739 Onan
                      745 0 & R Engines
                      747 Litton
                      757 Brinly-Hardy Co., Inc.
                      758 Emerson Electric
                      761 Whirlpool
                      767 Marvel
                      768 Technics (Matsushita)
                      769 Mercury Clutch Division
                      773 Marantz
                      775 Johnson
                      778 Comet Industries
                      785 General Power (Magna America Corp.)
                      789 DefiAnce
                      790 Frigid Ire
                      791 Tappan
                      793 Ford
                      798 Speed King
                      802 Baker Mfg Co.
                      809 AMF
                      815 Daewoo
                      831 Welso Inc/U.T.S.
                      832 Xerox
                      835 Roper
                      840 Friedrich
                      842 Haban Mfg.
                      846 Epson
                      850 Whirlpool (Chambers?)
                      854 White Farm Equipment Corp. (formerly Oliver
                      855 ILG
                      860 Eureka Company
                      864 Zenith
                      867 Climette
                      871 Smith Corona
                      879 Rheem/Rudd
                      900 Black and Decker
                      911 General Electric
                      917 Roper Corp. (American Yard Prod.
                      919 DeVilbiss
                      922 Original Tractor Cab Co.
                      923 Hewlett Packard
                      934 Century Mfg Co.
                      937 Sunbeam (now Air Cap Ind.)
                      950 Laser (V-TECH)
                      960 Caloric
                      973 Ryobi
                      987 Troy Bilt/Garden Way
                      988 Kubota
                      989 McCullogh
                      990 Ford
                      991 Lawnboy
                      2018 Furnas Electric (Reversing Switch)
                      7075 Prestolite Battery
                      7287 Emerson Electric
                      7296 Emerson Electric

                      Hand Tools - Danaher (before 1994 it was Stanley)

                      Comment


                      • #56
                        Re: 18 Volt Lithium-Ion Batteries - Ah rating situation

                        Disaster,useful bit of information thanks. Now that I know Roper made my Sears Lawn Tractor maybe I can get a drive belt from one of their distributors and not have to pay $40.00 to Sears again. I'll be saving this link you provided.

                        Comment


                        • #57
                          Re: 18 Volt Lithium-Ion Batteries - Ah rating situation

                          Originally posted by Frankiarmz View Post
                          Disaster,useful bit of information thanks. Now that I know Roper made my Sears Lawn Tractor maybe I can get a drive belt from one of their distributors and not have to pay $40.00 to Sears again. I'll be saving this link you provided.
                          You might find it is more expensive elsewhere! On the other hand, if you can find out the length you might find several brands selling the exact same belt cheaper.

                          It doesn't look like Sears still holds to this system. Perhaps it was dropped when they joined with Kmart. All the power tools start with 009...even the ones with other brand names like Bosch. Can't see any other part of the part number that is common between tools obviously made by the same manufacturer.

                          Comment


                          • #58
                            Re: 18 Volt Lithium-Ion Batteries - Ah rating situation

                            Disaster, I got my parts delivered today and the idler pulley and belt were a breeze to install. I checked the price of the parts on another site and the belt was the same price, idler pulley ten dollars cheaper. I like to stock spare parts here and there because I don't like being without the use of a machine, but aside from the drive and deck belts there's really too many parts to warehouse. I usually shop around for good deals but the leaves pile up fast here in CT, I emptied 48 bins this afternoon and that's only a few days worth.

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