115 Wh in a 9 V battery - Page 1
Forum section: electronics / general

author: PinheadBE
author_rank: Regular Contributor
timestamp: October 22, 2023, 11:07:23 am
content: Or how to power your e-car from .... what... a suitcase-sized battery ?

author: DavidAlfa
author_rank: Super Contributor
timestamp: October 22, 2023, 12:18:00 pm
content: Yeah...chinese Magic. Like 9999999mah 18650 cells.This is like idiot people, please just ignore them

author: Gyro
author_rank: Super Contributor
timestamp: October 22, 2023, 12:19:19 pm
content: If they want really big headline numbers then they really should start using uAh. The one with the most digits is automatically better!

author: SpecialK
author_rank: Regular Contributor
timestamp: October 22, 2023, 12:28:10 pm
content: It's "Full of" definitely.

author: Zenith
author_rank: Frequent Contributor
timestamp: October 22, 2023, 10:07:51 pm
content: To be filed with "2x Super Bright 2500000LM LED Tactical Torch". Yours for £13.49 complete with batteries and charger.A QI car headlight produces around 1500 lumen. 1200 lumen is going some for a LED torch with a single 18650. 2.5 million lumen? They might produce 250.

author: SiliconWizard
author_rank: Super Contributor
timestamp: October 23, 2023, 02:55:59 am
content: One extra fun factor among the others is the mention "usage time: 10h". Who knows what it's supposed to mean, but since they obviously target these batteries for people with no knowledge of basic physics, my guess is that they'll put an hyper-inflated advertised capacity (completely unrealistic) but then they put a mention that actually means something tangible to people: "usage time", whatever usage they mean who knows, but since they claim that the batteries are made for toys and remote controls, if you have a remote that only lasts 10h on a single charge, then probably these batteries are more like 12.8mAh than 12800.

author: DavidAlfa
author_rank: Super Contributor
timestamp: October 23, 2023, 03:55:26 am
content: I remember about 15 years ago when Ultrafire batteries appeared, I took it very seriously and never bought them!Who seriously thought adding "Fire" to a battery brand would be a good idea?It's like making "Megarust" car parts, "Fastsink" floaters or "Mr.Poison" food sauce!Quote from: SiliconWizard on October 23, 2023, 02:55:59 amIt's the lifespan! Though not clear if it's the battery's or your's by using these batteries, you never know! LOL.

author: Ben321
author_rank: Frequent Contributor
timestamp: October 23, 2023, 04:30:29 am
content: Quote from: PinheadBE on October 22, 2023, 11:07:23 amPossible it works. I mean it's only about 12 amp hours. That is one amp for 12 hours, or 12 amps for an hour. Not unexpected if internally it has lithium ion cells. Those things have a huge energy density. Anybody here actually test it?

author: Kean
author_rank: Unknown
timestamp: October 23, 2023, 06:57:09 am
content: Quote from: Ben321 on October 23, 2023, 04:30:29 amNo need to test it, that is nonsense. The only way you could get such high currents is at a very low voltage, but the battery chemistry has a pretty limited working voltage range.Current Lithium Ion chemistry maxes out at about 265Wh per kg, but in reality will be lower in consumer grade products -https://en.wikipedia.org/wiki/Lithium-ion_batteryA typical 9V battery weighs 45g (I am keeping it simple and just going by weight, not volume) -https://data.energizer.com/pdfs/522.pdfAssuming you can live with a 9V battery supplying only 3.6-4.2V, with this top of the line chemistry you will get no more than 12Wh, or 3.2Ah at 3.7V.Obviously a 9V battery is useless at that voltage, so the typical Li-Ion ones are 7.4V (8.4V max), and thus with two cells in series you get half or 1.6Ah max best case.Of course, no one makes such a top notch battery and the best you are likely to see around about half that again - typically 600-900mAh.I have not opened up a recent one, but I imagine they have a pair of 702040 cells, which would be rated in the 600-800mAh range. These are not high C rate cells.The 600mAh USB rechargeable 9V batteries I have actually come pretty close to that spec when tested at 50mA down to 7.0V (I think the rating is based on going to 5.0V LOL).The 800mAh labelled ones I have bought measured at less that 300mAh when tested in a similar way.

author: Zenith
author_rank: Frequent Contributor
timestamp: October 23, 2023, 09:10:22 am
content: Quote from: Ben321 on October 23, 2023, 04:30:29 amYou can buy USB rechargeable Li-ion PP3s on Amazon and the highest capacity they claim is 1300 mAh. I very much doubt they have that, particularly with any reasonable discharge regime. Looking at battery reviews where they measure the capacity, even op notch makers are optimistic when it comes to mAh claims. The batteries in question are advertised with a capacity ten times 1300 mAh and for about the same price. Believe it if you wish.Compare it with a top end 18650 cell, with a credible capacity of 3,600 mAh. They claim to have over three times that in PP3 form factor, which also has to house the USB socket and charger circuitry.

author: Ben321
author_rank: Frequent Contributor
timestamp: October 24, 2023, 09:53:15 pm
content: Quote from: Kean on October 23, 2023, 06:57:09 am3 li-ion cells in series, with a 9v voltage regulator (to keep the output from exceeding 9v) would work, right? With the way components are getting miniaturized these days, I wouldn't be surprised if they could fit all that into a 9v battery sized chassis.

author: SiliconWizard
author_rank: Super Contributor
timestamp: October 24, 2023, 10:12:21 pm
content: Quote from: Ben321 on October 23, 2023, 04:30:29 amNo, it's not.

author: kjr18
author_rank: Regular Contributor
timestamp: October 26, 2023, 08:17:52 am
content: Quote from: Ben321 on October 24, 2023, 09:53:15 pmWell, it's probably single cell with boost, or two in parallel, not in series as charging them would require more expensive circuit than simple TP4056 or TP4057 (smaller SOT23-6, 500mA version).

author: SL4P
author_rank: Super Contributor
timestamp: October 26, 2023, 08:38:22 am
content: It’s the Batteroo replacement.

author: PinheadBE
author_rank: Regular Contributor
timestamp: October 29, 2023, 11:40:03 pm
content: Even better now :

author: Mr.B
author_rank: Unknown
timestamp: October 30, 2023, 12:37:09 am
content: Quote from: Kean on October 23, 2023, 06:57:09 am@KeanI am looking for USB rechargeable 9V batteries.I want a reputable brand with realistic capacity advertised.Are you able to share the brand and source of the ones you quoted.Many thanks.

author: SiliconWizard
author_rank: Super Contributor
timestamp: October 30, 2023, 12:41:52 am
content: Quote from: PinheadBE on October 29, 2023, 11:40:03 pmThat's inflation for you!

author: Kean
author_rank: Unknown
timestamp: November 07, 2023, 12:37:22 am
content: Quote from: Mr.B on October 30, 2023, 12:37:09 amThe 600mAh ones that seem OK are ZNTER branded and charged via microUSB. I bought them in AliExpress via seller lvpower2011, and they also sell nice multi-way USB charge cables.The others were various brands including from memory Doublepow, and were generally garbage.Some had boost circuits which can be useful but remove the ability to judge remaining battery capacity.I have one of the "Kedanone 12800mAh" samples shown in the first post on the way. I will run a few tests, and then see what is inside and report back.The only other semi-decent one was the EBL branded ones recommended for use in the PDVS2mini - but those are specifically not USB rechargable.

author: Mr.B
author_rank: Unknown
timestamp: November 07, 2023, 12:44:31 am
content: Thanks @Kean.I am specifically looking for the PP3 type.I will get a few of the ZNTER ones from Ali.

author: Kean
author_rank: Unknown
timestamp: November 07, 2023, 07:02:05 am
content: Further to this now that I am in the office and the day is ending...The Doublepow rechargeable PP3s are what I have used in my PDVS2mini as I could not source the recommended EBC or Etinesan brands of non-USB charged Li-Ion PP3's. I don't seem to have done any test cycles on the Doublepow - or not anything I can find notes for - but I very much doubt they match the labelled 1000mAh spec based on my experience in the PDVS2mini which should draw 50mA (100mA max) and I don't believe I get 10 hours run time from a charge.I tried a few USB rechargeable ones over the last few years, and the ZNTER were the only decent ones of the ones I've tried. YMMV. I bought the ZNTER ones about 3 years ago and they still seem OK. The ZNTER that I had on the bench was dead after not being touched for a few months. I charged it up this afternoon (charges at 500mA) and it now reads 9.1V - so it clearly is one that has a boost circuit which I had forgotten, and thus explains why it was dead from self discharge. I am running a 50mA discharge test on it now (reading 9.05V) and will edit this later with the result.One of the non-English labelled PP3s is a microUSB chargeable Li-Ion but also garbage. It can light up the 3 green LED indicators, but struggled to give 250mAh compared to the labelled 800mAh. I think it came from Banggood several years ago so not a current model. I used it in one of my DMMs and it was really annoying so I switched back to an Energizer alkaline.The really terrible PP3s I was thinking about were branded GTL and are actually are NiMH. Labelled 900mAh but at best I've got 70mAh from them in testing. And they are suspiciously lighter weight.

author: Kean
author_rank: Unknown
timestamp: November 08, 2023, 04:58:51 am
content: Update: The discharge test on the ZNTER gave me 560mAh which is +/-2% of what I got the last couple of tests. Close to the rated 600mAh which is possibly based on less than 50mA discharge, and this battery is about 3.5 years old with intermittent use. The output stayed at approx 9.05V through the discharge cycle and then dropped to 0V in protection mode. Two seconds of charge got it out of protection mode and returned it to 9.05V. My other ZNTER PP3 is almost spot on 9.00V.The sample "Kedanone 12800mAh" battery is still on the way from China. Once it arrives I will post another update after testing it & investigating its internals.

author: Kean
author_rank: Unknown
timestamp: November 28, 2023, 02:05:09 am
content: The sample Kedanone 9V "12800mAh" cell from AliExpress arrived late last week.I charged it up via USB C cable, and left it on load overnight.Starting voltage was 9.1V and under 50mA load it stayed at 9.05V until a sudden drop terminating the discharge giving 340mAh.It had recovered voltage again to 9.1V and gave me another 70mAh - so a total of just 410mAh.Basically what I expected - typical or slightly below average capacity, and totally fake specification.I have it on charge again now and will do another cycle before I tear it apart to see the guts.

author: SiliconWizard
author_rank: Super Contributor
timestamp: November 28, 2023, 02:22:15 am
content: Shocking.