Capacity of cheap NiMH 6f22 battery from aliexpress - Page 1
Forum section: electronics / general

author: myf
author_rank: Regular Contributor
timestamp: November 16, 2018, 07:11:45 pm
content: Hello,I'm looking for building little games in a small box with leds, switchs and so. It must run under 9V because 5V = 4x1.2 or 6V may be too low...So I might use one 6F22 battery, for low use, less than 50mA and during short time, maybe 1h per week...The description of theses rechargeable batteries are fine for this use, but do you have idea of their actual capacity (at 50mA) and the number of refills they accept.I will not buy them if them capacity is only 80 mAh or if they can only be recharged two or three times. Varta batteries (and serious trademarks) will be of course fine, but they are 3 times more expensive!http://www.aliexpress.com/item/2pcs-PALO-300mAh-9V-6F22-Battery-Ni-MH-NiMH-Rechargeable-Battery-3A-Charging-Current-for-Multimeter/32818357992.htmlThere are also lithium-ion batteries, but I they are more dangerous, and more difficult to charge. So I prefer low-tech NiMH batteries.Many thanks for your advice and help !

author: thm_w
author_rank: Super Contributor
timestamp: November 16, 2018, 11:34:41 pm
content: nimh should be 400-500 recharge cycles, similar to li-ion.It is unlikely you will find someone here that has purchased that specific battery, but it looks decent enough, I would expect 2-300mAh.https://lygte-info.dk/review/batteries9V/Common9VIndividualTest%20UK.htmlhttps://lygte-info.dk/review/batteries9V/Soshine%209V%20LiIon%20650mAh%20(White)%20UK.htmlPersonally I am a fan of the 9V li-ion (second link), it is chargeable with a standard low current 9V charger.

author: rdl
author_rank: Super Contributor
timestamp: November 25, 2018, 06:44:59 pm
content: I've been using EBL brand Lithium Ion to replace regular 9 volt batteries. I tried their NiMH at first, but the capacity isn't even close to alkaline. While I haven't actually measured the capacity of the Li-ion, I don't see any real difference in actual usage compared to alkaline type. The EBL batteries and charger are easy to find and not too expensive on ebay if that is an option for you.https://www.ebay.com/itm/EBL-6F22-9V-600mAh-Li-ion-Rechargeable-Battery-2-Pack-9-Volt-Charger/371317748680

author: myf
author_rank: Regular Contributor
timestamp: January 05, 2020, 06:46:02 pm
content: Hello,Last year, I bought these palo nimh accumulators and I measured their capacity. The 4 accumulators of the first series contain approximately 0.16 Ah and the 2 of the second series contain approximately 0.14 Ah. The Foxter accumulator bought in the Leclerc hypermarket claims 0.2 Ah and contains (a little more) 0.2 Ah for 8 euros (=usd 9).The 9v-6f22 one use battery ranges from 0.23 Ah to 0.56 Ah.This first article explains the method and presents graphics, the second explains the method I use:http://www.usinages.com/threads/capacite-de-piles-et-daccumulateurs-rectangulaires-de-9v.127600/http://www.usinages.com/threads/experiences-delectronique-sous-linux-ut61-et-usbrelay.127868/Thank you for your previous answers !F.

author: benryanau
author_rank: Contributor
timestamp: March 14, 2020, 07:17:52 am
content: Few years ago now, but bought a variety of cheapish nimh-based PP9's. Nothing scientific to offer just that I wrote them off as a failed experiment.Apparently some makes of Lipo-based PP9's are well-made good bits of kit - seek out a few teardown reviews that should help.I wouldn't stress safety, teardown usually tells the story there and newer chemistries/designs (and cell design objectives) make it non-issue for most applications.Let us know how you go

author: coppercone2
author_rank: Super Contributor
timestamp: March 22, 2020, 03:52:05 am
content: I think good fresh brand name NiMH batteries are actually a good investment

author: Psi
author_rank: Super Contributor
timestamp: March 22, 2020, 06:35:38 am
content: Rechargeable 9V batteries are usually quite a bit less capacity than your normal dry-cell or alkaline ones.100-200mAh is pretty common vs 500mAh for non-rechargeable

author: mariush
author_rank: Super Contributor
timestamp: March 22, 2020, 08:27:23 am
content: Can you give more details about what's the actual voltage your device actually needs?Why not go with AAA batteries, you could put 4 of them in just a bit more space than what a 9v battery uses and rechargeable AAA batteries have around 500-700 mAhAlternatively, why not use a cheap voltage doubler IC to double the voltage? If needed a low drop linear regulator can stabilize the voltage to 5v.Charge pump regulators only need 2-3 ceramic capacitors and a couple diodes (preferrably low drop diodes), nothing complicated.You can then use 2 AA batteries which can have up to 2500-2800mAh of charge or 2 x AAA batteries with 800-1200mAh charge, and boost the voltage to 4.5v..5v... and user would just have to replace 2 batteries at a time.Or, you could use 3 AAA or 3 AA batteries and the doubler would bring the voltage to around 6.5-7v ... and you can use a very low drop linear regulator to get the voltage to 5v ... a linear regulator would add a few cents to the cost of your device.You said the currents are low, so you could use for example:MAX1720 : > 50mA 1.5v..5.5v charge pump/doubler/triplerDigikey: 0.6$ @ 10 :https://www.digikey.com/product-detail/en/on-semiconductor/MAX1720EUTG/MAX1720EUTGOSCT-ND/2705019LCSC : 0.2$ @ 10 :https://lcsc.com/product-detail/DC-DC-Converters_ON-Semiconductor-ON-Semiconductor-MAX1720EUTG_C70466.htmlDatasheet:https://www.onsemi.com/pub/Collateral/MAX1720-D.PDFSee pages 9 and 10 ... you could even use it as voltage tripler, but you'd have to keep the current at around 20mA or lower.LCSC has a lot of cheap charge pumps for pennies.For example, if you don't mind using 3 batteries because the chip need min. 2.7v, you can use TX4314 to get ~4.95v up to 300mA (100mA with 3v+) :https://lcsc.com/product-detail/DC-DC-Converters_XDS-TX4314_C329270.htmlIF you want a more common chip you could possibly source from other stores (at a higher price) you have TPS60400 and TSP60403 , 1.8v min input voltage, 60mA current :https://lcsc.com/product-detail/DC-DC-Converters_Texas-Instruments_TPS60400DBVR_Texas-Instruments-Texas-Instruments-TPS60400DBVR_C9839.htmlhttps://lcsc.com/product-detail/DC-DC-Converters_Texas-Instruments_TPS60403DBVR_Texas-Instruments-Texas-Instruments-TPS60403DBVR_C11338.htmlIf you go with 9v batteries, you're still gonna have to use a switching regulator, or you'll just throw out a lot of your battery with linear regulators, it's a shame... and they're expensive if not rechargeable, and rechargeable ones are slow to charge.ps... and you could use two of them in parallel if you need more than 50mA the max1720 can give you, at 0.2$ plus around 0.1$ for the 2 diodes and ceramic capacitors ... you're looking at 0.3-0.4$ in total for a doubler regulator.You're adding to the price of the device but you're saving in battery cost and easy of recharge... you can buy rechargeable AA batteries for around 1...1.5$ each ... while you'd pay 8$ for a 2 pack of 9v batteries.