On Wed, 07 Nov 2018 14:38:39 -0500, Ingvald44 <noone@nowhere.com> wrote:>>The 18650 batts are interesting. Some are given ridiculous ratings..>9000 mah is one. They check out at around 1000 mah. Good ones are >actually 3000 mah or so, get the unprotected ones so you can draw >current without it cutting out. I have a 20 volt pack I put together >for a Black and Decker leaf blower. It will now blow off my whole >lawn from one charge. I use a balance charger to keep it happy.Yep. Here's the discharge curves for two of eBay's cheapest junk 18650 cells, rated at 5800 and 5000 ma-hr, which is science fiction. Note that I tested at 1.5A so that I don't have to wait forever for the test to complete: <http://www.learnbydestroying.com/jeffl/battery-tests/18650.jpg> I would give them 1000 ma-hr and 900 ma-hr respectively. I've seen worse. I use a West Mountain Radio CBA-II for generating the curves: <http://www.learnbydestroying.com/jeffl/LiPo/Ultrafire%2018650%20test.jpg> <http://www.westmountainradio.com/cba.php> I routinely test cells that I pull out of laptop batteries that measure around 2000 ma-hr. Unfortunately, I can't seem to find where I buried that data or graphs. -- Jeff Liebermann jeffl@cruzio.com 150 Felker St #D http://www.LearnByDestroying.com Santa Cruz CA 95060 http://802.11junk.com Skype: JeffLiebermann AE6KS 831-336-2558
Using cordless tool batteries to power a drone
Started by ●November 7, 2018
Reply by ●November 7, 20182018-11-07
Reply by ●November 7, 20182018-11-07
On Wed, 07 Nov 2018 19:26:31 -0500, Martin Riddle <martin_ridd@verizon.net> wrote:>>More later, after I'm done with todays plumbing project.>Why do plumbing projects alway come up in November?Actually, the timing was fairly good for me. The story on this one is rather interesting. I help maintain computers, phones, internet, and plumbing in a small office building owned by a customer/friend[1]. There are four bathrooms, each with a very expensive metered faucet on the sink: <https://www.chicagofaucet.com/RepairDrawings/pdf/RP3501-4E39VPABCP.pdf> Three years after installation, all four metered faucets failed to automatically turn off the water. When I tore one apart, I discovered that there was a Schrader bicycle tire valve screwed into the center of the "metering valve cartridge" (item #7) that had failed because the valve spring had rusted away. Since bicycle valves are normally not used in this manner and normally not immersed in water, I was worried that the proper spring might be made from stainless steel or something equally rust resistant. A call to tech support informed me that the valve was not user replaceable and that the assembly would cost me only $36 on Amazon. No thanks. I went to my car, dug though my box of bicycle parts, found a new tire valve, and had it working in a few minutes. I'll fix the other faucets tomorrow and determine the spring material over the next week or so. [1] Customers pay me. Friends do not. Otherwise, they're the same. -- Jeff Liebermann jeffl@cruzio.com 150 Felker St #D http://www.LearnByDestroying.com Santa Cruz CA 95060 http://802.11junk.com Skype: JeffLiebermann AE6KS 831-336-2558
Reply by ●November 7, 20182018-11-07
Panasonic 18650s have been rated at no less than 3400 mA hours, for years. I have been using two of them, for at least 2 years. Their capacity is many times verified to be over 3000 mA hours. I just noticed this BS post is from the persistent nym-shifting troll known as "AlwaysWrong". Is it really that stupid/ignorant? -- DLUNU <DecadentLinuxUserNumeroUno DLU.org> wrote:> Path: eternal-september.org!reader02.eternal-september.org!feeder.eternal-september.org!aioe.org!.POSTED!not-for-mail > From: DLUNU <DecadentLinuxUserNumeroUno DLU.org> > Newsgroups: sci.electronics.design > Subject: Re: Using cordless tool batteries to power a drone > Date: Wed, 7 Nov 2018 19:31:48 +0000 (UTC) > Organization: DLU > Lines: 65 > Message-ID: <prvej4$fsu$1 gioia.aioe.org> > References: <prv73u$g3h$1 dont-email.me> <prvact$87v$1 gioia.aioe.org> > NNTP-Posting-Host: 2OGt5QfTQMwQyNuExg78MA.user.gioia.aioe.org > X-Complaints-To: abuse aioe.org > User-Agent: Xnews/5.04.25 > X-Notice: Filtered by postfilter v. 0.8.3 > Xref: reader02.eternal-september.org sci.electronics.design:528348 > > <698839253X6D445TD nospam.org> wrote in > news:prvact$87v$1 gioia.aioe.org: > >> On a sunny day (Wed, 7 Nov 2018 17:24:14 -0000 (UTC)) it happened John >> Doe <always.look message.header> wrote in >> <prv73u$g3h$1 dont-email.me>: >> >>>Disclaimer: I'm not looking for the best drone power supply. I enjoy >>>using high quality branded products. Of course it's all made in China. >>>That is IMO a good reason to pay close attention to branding. I intend >>>to pay VERY close attention to my battery pack temperature, and to >>>take the endeavor very slowly. >>> >>>I have a spare Dewalt 20 V Max 6 amp hour battery, and a load of new >>>18650 batteries from an electric monowheel/unicycle I bought mainly >>>for the experience. >>> >>>I would bet the 18650s in Dewalt's 9 amp hour FLEX VOLT would work, >>>for $200. I suppose trying to find those batteries would be impossible >>>due to lack of labeling. >>> >>>I suppose one way to guess at discharge rates is to look at the >>>application the battery is meant for, the run time of the device. But >>>of course data is preferable. >>> >>>Any resource for discharge rates of 18650 batteries? >>> >>>Thanks. >> >> Interesting, I have been trying just that, >> those batteries to power my Hubsan drone. >> First; there are many makes of 18650 batteries, with vastly different >> specs. I bought 3 of the best I could find locally (expensive) was >> sold as 'Sony' but I am sure it is some Chinese copy, >> Anyways tried 2 in series and that gave me shorter flight time than 2 >> cell lipos. Tried 3 in series with an ebay 10A stepdown switching >> regulator and the thing was to heavy to fly, or the regulator limited >> at the >10A current required. There is a youtube video of someone >> doing the same thing. I still have the batteries but am back to lipos, >> And 2 lipos in parallel works for up to 30 minutes it seems. >> >> So look up the specs of your battery.. >> >> BTW I bought some big power resistors and use a DC ampere clamp-on >> meter for battery duration tests, like this: >> http://panteltje.com/pub/power_resistors_IMG_6291.JPG >> big heatsink, resistors in series or parallel, 100 W each.. >> http://panteltje.com/pub/big_heatsink_IMG_6292.JPG >> >> Or measure real drone current: >> http://panteltje.com/pub/hubsan_h501s_current_test_full_throttle_IMG_ > 6 >> 290.JPG >> Posted some battery results in August 2017 to the hubsan group. >> >> >> >> > > The 18650s are all made by maybee three major battery makers and > Panasonic is the best and was the originally contracted maker. The > units being dubbed any higher than 1200 mA/h are bogus. > > If it were true, all cars would be electric by now. And powered by > little 4X original spec 18650s. >
Reply by ●November 7, 20182018-11-07
Jeff Liebermann <jeffl@cruzio.com> wrote: ... Your claim about capacity versus weight does not translate to the real world. Two 18650 I have are verified to be approximately 2400 and 3200 ma hours. Their weights are 43.4 and 45.9 grams. The capacity of 18650 does not follow their weight. The interesting thing about cordless tool batteries is their goal... high-capacity, high discharge rate (especially with Dewalt FLEX), and less weight. Apparently there are other factors, like number of recharges.
Reply by ●November 8, 20182018-11-08
On 07/11/2018 17:24, John Doe wrote:> Disclaimer: I'm not looking for the best drone power supply. I enjoy > using high quality branded products. Of course it's all made in China. > That is IMO a good reason to pay close attention to branding. I intend > to pay VERY close attention to my battery pack temperature, and to take > the endeavor very slowly. > > I have a spare Dewalt 20 V Max 6 amp hour battery, and a load of new > 18650 batteries from an electric monowheel/unicycle I bought mainly for > the experience. > > I would bet the 18650s in Dewalt's 9 amp hour FLEX VOLT would work, for > $200. I suppose trying to find those batteries would be impossible due > to lack of labeling. > > I suppose one way to guess at discharge rates is to look at the > application the battery is meant for, the run time of the device. But of > course data is preferable. > > Any resource for discharge rates of 18650 batteries? > > Thanks. >Stick with hobby Lipo packs... forget playing with single 18650 cells and making your own packs. The 18650 maket is full of low grade chinese exports.. --- This email has been checked for viruses by Avast antivirus software. https://www.avast.com/antivirus
Reply by ●November 8, 20182018-11-08
John Doe <always.look@message.header> wrote in news:ps09hn$i32$1@dont- email.me:> Panasonic 18650s have been rated at no less than 3400 mA hours, for > years. I have been using two of them, for at least 2 years. Their > capacity is many times verified to be over 3000 mA hours. > > I just noticed this BS post is from the persistent nym-shifting > troll known as "AlwaysWrong". Is it really that stupid/ignorant? >Geez yer an abject idiot. YOU, motherfucker, are the only fucktard in this group deserving an "it" moniker, you subhuman scum. My post was to make aware that there are false claims out there. So my number of 1200 mAh was supposed to be 3000mAh. The point being made was that there are no 10000 mAh units or others that we always see being advertised. Goddamn, motherfucker, get off your high horse little boy. And no, fuckhead, you won't be powering your high horse with a cordless drill either!
Reply by ●November 8, 20182018-11-08
A lame excuse for being AlwaysWrong, from the chronic nym-shifting troll and foulmouthed tough-guy-wannabe on the Internet... -- DLUNU <DecadentLinuxUserNumeroUno DLU.org> wrote:> Path: eternal-september.org!reader02.eternal-september.org!feeder.eternal-september.org!aioe.org!.POSTED!not-for-mail > From: DLUNU <DecadentLinuxUserNumeroUno DLU.org> > Newsgroups: sci.electronics.design,free.spam > Subject: Re: Using cordless tool batteries to power a drone > Date: Thu, 8 Nov 2018 14:27:54 +0000 (UTC) > Organization: DLU > Lines: 24 > Message-ID: <ps1h59$1r9v$1 gioia.aioe.org> > References: <prv73u$g3h$1 dont-email.me> <prvact$87v$1 gioia.aioe.org> <prvej4$fsu$1 gioia.aioe.org> <ps09hn$i32$1 dont-email.me> > NNTP-Posting-Host: 2OGt5QfTQMwQyNuExg78MA.user.gioia.aioe.org > X-Complaints-To: abuse aioe.org > User-Agent: Xnews/5.04.25 > X-Notice: Filtered by postfilter v. 0.8.3 > Xref: reader02.eternal-september.org sci.electronics.design:528411 free.spam:11969 > > John Doe <always.look message.header> wrote in news:ps09hn$i32$1 dont- > email.me: > >> Panasonic 18650s have been rated at no less than 3400 mA hours, for >> years. I have been using two of them, for at least 2 years. Their >> capacity is many times verified to be over 3000 mA hours. >> >> I just noticed this BS post is from the persistent nym-shifting >> troll known as "AlwaysWrong". Is it really that stupid/ignorant? >> > > Geez yer an abject idiot. YOU, motherfucker, are the only fucktard in > this group deserving an "it" moniker, you subhuman scum. > > My post was to make aware that there are false claims out there. > > So my number of 1200 mAh was supposed to be 3000mAh. The point being > made was that there are no 10000 mAh units or others that we always see > being advertised. > > Goddamn, motherfucker, get off your high horse little boy. > > And no, fuckhead, you won't be powering your high horse with a > cordless drill either! > >
Reply by ●November 8, 20182018-11-08
TTman <kraken.sankey@gmail.com> wrote:> John Doe wrote:>> Disclaimer: I'm not looking for the best drone power supply. I >> enjoy using high quality branded products. Of course it's all >> made in China. That is IMO a good reason to pay close attention >> to branding. I intend to pay VERY close attention to my battery >> pack temperature, and to take the endeavor very slowly. >> >> I have a spare Dewalt 20 V Max 6 amp hour battery, and a load of >> new 18650 batteries from an electric monowheel/unicycle I bought >> mainly for the experience. >> >> I would bet the 18650s in Dewalt's 9 amp hour FLEX VOLT would >> work, for $200. I suppose trying to find those batteries would be >> impossible due to lack of labeling. >> >> I suppose one way to guess at discharge rates is to look at the >> application the battery is meant for, the run time of the device. >> But of course data is preferable. >> >> Any resource for discharge rates of 18650 batteries?> Stick with hobby Lipo packs... forget playing with single 18650 > cells and making your own packs. The 18650 maket is full of low > grade chinese exports..Yep, even on Amazon, and of course on fleaBay. But an experienced cognizant buyer can sort out the BS. Knowing how to vet a seller on fleaBay helps a lot. Avoid anything unrealistic. And expect to get what you pay for. I doubt lipos are any different. I would bet some popular lipos are not the milliamp hour rating they are sold as. My first test... The electric unicycle batteries stayed cool as a cucumber. Without propellers, almost no load. Will see when there is a normal load, after a break. My 18650x3 (removable, insertable) complete battery pack weighs 164.3 g. If I use 18650s, I suspect a better battery is needed. I can get last year's 6 amp hour FLEXVOLT new for $100. Ordered Torx security screwdriver set (Titan 12710) to disassemble my big and heavy 6 amp hour 20 volt MAX Dewalt battery, maybe. A 3s 2200 mA hour lipo weighs 183 g??? https://www.trossenrobotics.com/3s-11v-2200mah-25c-lipo-battery One thing users are attracted to is the recharge rate. I prefer to slowly recharge batteries. I would rather have more batteries.
Reply by ●November 9, 20182018-11-09
John Doe <always.look@message.header> wrote in news:ps2p37$dp2$1@dont- email.me:> A lame excuse for being AlwaysWrong, from the chronic nym-shifting > troll and foulmouthed tough-guy-wannabe on the Internet... >Fuck You, mindless child. Go play with your drill motor.
Reply by ●November 9, 20182018-11-09
John Doe wrote>A 3s 2200 mA hour lipo weighs 183 g???Yes, just measured a 40C one at 190 g inclusive huge terminal blocks, see picture below. Those lipos are cool, 40C, you can start a car with one. I used one to replace the sealed lead acid in my tire pump compressor. Smaller, lighter, no leaking, I have several lipo chargers, those charge at low current, Small ones I charge on the lab supply. And all that lipo stuff is ebay, just read the reviews and recommendation in the RC groups to find the right model / seller. These are from ebay and work for me: http://panteltje.com/pub/3cell_40C_ebay_lipo_IMG_6682.JPG
