Need D size, 32650, 26650, 18650 or AAA, AA rechargable batteries with converter suggestions (India)

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nOne
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Need D size, 32650, 26650, 18650 or AAA, AA rechargable batteries with converter suggestions (India)

Hi.

I'm new to this forum. I am from India.
Please don't mind my English and correct me whenever I'm wrong.
Before joining I have checked HKJ reviews but didn't read completely. Then I decided to join this forum and clear my doubts.

 

I need 2 to 4, D sized Li-ion battery, which is going to replace existing D size Zinc–carbon battery.
Also I need 2 to 4, 18650 size Li-ion battery. It's for DIY experiments and some random stuff.

 

I have a Gas Geyser which requires two D size batteries (connection in series - 1.5 + 1.5 total 3v).
I want to replace it with rechargeable batteries. I have checked battery chemistry and I think Li-ion will be better than NiMH. But there is voltage problem as Li-ion have 3.7v.
According to Wikipedia, D size is similar to 32650 Li-ion battery size, but no similar voltage. There is 0.7v difference between those Li-ion and Zinc–carbon batteries.
Will this 0.7v difference can cause damage to Gas Geyser arc production circuit?
I want to know best long lasting battery in the budget.

 

Also there is availability issue for 32650 battery in India, but 26650 is available. I'm still searching local markets but there is no guarantee that it will be genuine original battery.
I have checked D size converters AAA, AA, 18650, 26650. If total cost of battery and converter is within my budget compared to similar D size battery then I can buy small size battery with converter.

 

I have used 18650 batteries and found so many fake batteries, used batteries being sold in the markets. I need genuine original battery.
I have selected LG MJ1 after watching YouTube review. I don't know how many I will purchase in future. But as of now I will use 2 to 4.
But I have 1 generic 18650 purchased which is working fine not great though, before that I have used 4 18650 batteries removed from local power bank.
18650 battery will be used for DIY experiments, like arc plasma gas lighter circuit (which is yet to receive from banggood), emergency led bulb and others etc.

 

So, summing up...

  1. Which 2-4 batteries to choose for my gas geyser, D size, 32650, 26650 or 18650, or AA, AAA with D size converter or anything else? (if you are suggesting 4 batteries then I can purchase 2 batteries of same brand and 2 batteries of other, if it's difficult to choose from.)
  2. And which 18650 battery around 3-5 volt, 3-5 amp max output and long lasting battery? LG MJ1
  3. Also please provide genuine original battery seller purchase links which can ship to Mumbai, India. Aliexpress doesn't ship to India. I have not yet to received existing order from Banggood in India (2 Weeks completed).
Edited by: nOne on 10/23/2021 - 07:56
raccoon city
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I hope you have fun here, nOne!

213_milla

raccoon city
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For AA and AAA, I recommend Eneloops.

For D batteries, I recommend 3 AA to D battery adapters, like this:

https://www.amazon.com/dp/B01MEF4K44

 

For lithium-ion cells, check out this thread to see who ships to India:

https://budgetlightforum.com/node/63587

Rexlion
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The lithium ion cells are nominally 3.7V but in reality they are 4.2V at full charge. Voltage declines as charge declines, so when it’s at 3.7V it is depleted by about 1/2 (if I recall correctly). Two such cells in series would reach as high as 8.4V at full charge. A single cell with a metal spacer (a ‘dummy’ cell) could be used to provide only the voltage of a single such cell, but that voltage might still ruin your device. LiFePO4 chemistry cells (3V nominal, 3.6V fully charged) might be a somewhat better alternative, but I don’t know if they are made in 32650 or similar size.

I would recommend using two NiMH rechargeable D cells, such as Tenergy Centura. They would give you about 10Ah of current which is more than you’ll get out of the 32650. You might also be able to use two AA NiMH cells (Eneloops are the best) in AA-to-D adapter cases, but if your device draws too much current at one time it could make the voltage sag too much from the AA cells.

== We save the planet from darkness ==

nOne
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raccoon city wrote:

I hope you have fun here, nOne!

Yes. Thank you.
raccoon city wrote:

For AA and AAA, I recommend Eneloops.

For D batteries, I recommend 3 AA to D battery adapters, like this:
https://www.amazon.com/dp/B01MEF4K44

For lithium-ion cells, check out this thread to see who ships to India:
https://budgetlightforum.com/node/63587


Eneloop or eneloop pro?
https://www.amazon.in/dp/B00JHKSL28/
https://www.amazon.in/dp/B00KE5NTLS/
https://www.amazon.in/dp/B017J8EWH2/

3 AA to D adapter little expensive online. I need to check locally for current prices.

Need 1 more suggestion for 2032 batteries. Panasonic or Duracell?
https://www.amazon.in/dp/B00LVMTA2A/
https://www.amazon.in/dp/B08Y1TQ8K7

I have checked that thread before joining too, there was no specific India website.
But for shipping thing I need to register every site, it would be easy if someone from India can provide exact link.

Can you suggest exact brand model no for 18650 batteries? it will be easier.

Rexlion wrote:
The lithium ion cells are nominally 3.7V but in reality they are 4.2V at full charge. Voltage declines as charge declines, so when it's at 3.7V it is depleted by about 1/2 (if I recall correctly). Two such cells in series would reach as high as 8.4V at full charge. A single cell with a metal spacer (a 'dummy' cell) could be used to provide only the voltage of a single such cell, but that voltage might still ruin your device. LiFePO4 chemistry cells (3V nominal, 3.6V fully charged) might be a somewhat better alternative, but I don't know if they are made in 32650 or similar size. I would recommend using two NiMH rechargeable D cells, such as Tenergy Centura. They would give you about 10Ah of current which is more than you'll get out of the 32650. You might also be able to use two AA NiMH cells (Eneloops are the best) in AA-to-D adapter cases, but if your device draws too much current at one time it could make the voltage sag too much from the AA cells.

Thank you for detailed info. That was my exact concern about d cell adapter.
But which eneloop is alkaline and which is nimh? And which will be better?

Can you provide D size rechargeable battery link? I couldn't find Tenergy Centura with 10Ah.
https://www.amazon.in/
https://www.flipkart.com/

Rexlion
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My memory was off; the Centura D is 8Ah, not 10.

All Eneloop (name brand) cells I’ve ever seen are rechargeable NiMH, and low self discharge to boot. I assume you are trying to get away from using disposable cells such as alkalines.

== We save the planet from darkness ==

xxo
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For AAA and AA’s I like Fujitsu NiMH – these are the same as Japanese eneloops (Fujitsu makes eneloops in their factory). Eneloops are fine if you make sure that they are made in Japan and are not fakes (a lot of them are fake and some eneloops are now made in China).

For C and D cells, low self discharge NiMH from Soshine work well, Tenergy centuras are OK too but have a little lower capacity.

For Li-ion 14500, 18650, 21700 and 26650’s, I like protected Keeppower cells.

Correllux
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I think before you go any further you need to learn what requirements that device has. An email to the manufacturer or sales distributor might get you the information you need. First, you definitely need to know the acceptable voltage range of the power circuit. Some devices accept a range and can handle over-voltage to a small degree…some can’t and you risk blowing fuses or damaging the components. Whether the batteries are set up in series or parallel can give you a hint but not confirmation. Second, you need to know approximately how much current the device uses. If it isn’t a lot and if it can handle 4.2v then perhaps you could run a single lithium-ion cell in there although that may not be as much capacity as the two D-cells provide. If the device handles lower voltage ok, then a couple of the good quality NiMH D-cells might be your best option – the good ones have 9,000mAh or more and can handle typical current draw on boards without too much voltage sag. Those are around 1.45v off the charger and usually peter out around 1.0 to 1.1 volts. If the device gets unhappy with less than 1.3 or 1.2 volts then NiMH is probably not a good option, but you could just recharge them more frequently if they aren’t draining too quickly.

I wouldn’t shop for cells before you know this basic important information about the device. They seem expensive enough (about $100 USD) that I wouldn’t want to risk damaging them. If there are fuses, sometimes those are surprisingly expensive, too, depending on what type and size.

nOne
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Rexlion wrote:
My memory was off; the Centura D is 8Ah, not 10. All Eneloop (name brand) cells I've ever seen are rechargeable NiMH, and low self discharge to boot. I assume you are trying to get away from using disposable cells such as alkalines.

Tenergy Premium D 10000mAh NiMH Rechargeable Batteries, 4pk - Tenergy
Tenergy Centura D 8000mAh NiMH Rechargeable Batteries, 4pk - Tenergy
it is so much confusing, which to choose. Not only from this brand and others too.
EBL D Size Rechargeable Batteries D Cell 10000 mAh NiMH Battery (Multicolour) - 2 Counts : Amazon.in: Home Improvement
BONAI Rechargeable D Size Batteries 10000mAh 1.2V Ni-MH with High Capacity (4 Pack) : Amazon.in: Electronics
As per my application I don't think I need high discharge battery for Gas Geyser compared to existing Zinc–carbon (which lasts 70 days, daily 10 uses, 5 sec/use)
xxo wrote:
For AAA and AA's I like Fujitsu NiMH - these are the same as Japanese eneloops (Fujitsu makes eneloops in their factory). Eneloops are fine if you make sure that they are made in Japan and are not fakes (a lot of them are fake and some eneloops are now made in China). For C and D cells, low self discharge NiMH from Soshine work well, Tenergy centuras are OK too but have a little lower capacity. For Li-ion 14500, 18650, 21700 and 26650's, I like protected Keeppower cells.

Fujitsu NiMH, interesting info. Thank you for sharing.
Original eneloop available here in India. I will buy that only.
Panasonic eneloop AAA Rechargeable Battery, Pack of 4 : Amazon.in: Electronics
Panasonic eneloop AAA800 mAh Battery - Panasonic : Flipkart.com
Panasonic eneloop AA Rechargeable Battery, Pack of 4 : Amazon.in: Electronics
Panasonic Eneloop AA 2000 mAH Battery - Panasonic : Flipkart.com
Panasonic eneloop Pro AA Ni-MH Rechargeable Battery with 2550 mAh Capacity - Pack of 4 - BK-3HCCE/4BN : Amazon.in: Electronics
Panasonic Eneloop Pro Battery - Panasonic : Flipkart.com

For c and d size: (D size batteries are 2200–12000 mAh as per Wiki)
You are suggesting this Soshine 11000 mAh
Soshine D/R20 Size Rechargeable Batteries NiMH 11000mAh - Soshine
Is this will be good or Tenergy premium, centura or EBL or bonai??

Correllux wrote:
I think before you go any further you need to learn what requirements that device has. An email to the manufacturer or sales distributor might get you the information you need. First, you definitely need to know the acceptable voltage range of the power circuit. Some devices accept a range and can handle over-voltage to a small degree...some can't and you risk blowing fuses or damaging the components. Whether the batteries are set up in series or parallel can give you a hint but not confirmation. Second, you need to know approximately how much current the device uses. If it isn't a lot and if it can handle 4.2v then perhaps you could run a single lithium-ion cell in there although that may not be as much capacity as the two D-cells provide. If the device handles lower voltage ok, then a couple of the good quality NiMH D-cells might be your best option - the good ones have 9,000mAh or more and can handle typical current draw on boards without too much voltage sag. Those are around 1.45v off the charger and usually peter out around 1.0 to 1.1 volts. If the device gets unhappy with less than 1.3 or 1.2 volts then NiMH is probably not a good option, but you could just recharge them more frequently if they aren't draining too quickly. I wouldn't shop for cells before you know this basic important information about the device. They seem expensive enough (about $100 USD) that I wouldn't want to risk damaging them. If there are fuses, sometimes those are surprisingly expensive, too, depending on what type and size.

Arc generator or gas lighter circuit, I checked with 5v 1A DC adapter which works good, but i fear about the voltage. So NiMH is good for it 1.2+1.2=2.4v compared regular 1.5+1.5=3v.
I tried 5v 1A charger worked, 5v 2A worked (fast gas lighter generation) it did not worked above that on 9v and on as I checked connecting direct wires with DC adapter.
I am sure that batteries are in series, as I can see the internal connections and +ve and -ve terminals of battery with naked eye, after removing the geyser cabinet.
I don't know how much current it draws, I think max 2A but not sure.
And about circuit protection, for gas geyser, generic and original lighting circuit is easily available locally so no worry. Also protections are provided which worked as well as I check voltage 9v (18 watt charger) it didn't worked and nothing happened to circuit or geyser. So all well.

Any suggestion for D cell NiMH other than these - Soshine, Tenergy premium, Tenergy centura, EBL, bonai.

 

18650 battery suggestions remaining. Some of them I selected Indian online store,
primary applications will be 3V-5V 3A diy arc generator, arc plasma gas lighter circuit, replacing very old Dell D530 laptop battery 6 li-ion cell, 11.1V, 56WH (year 2007) (Type M9014)
secondary applications diy power bank and some other stuffs.
3.7V 2600mAH Lithium Polymer (Li-Po) Battery - 18650 Model - Samsung
Li-Po Battery-3.7V/2600mAH-Model 18650-Samsung | Sharvielectronics: Best Online Electronic Products Bangalore
3.7V 2600mAH Lithium Polymer (Li-Po) Battery - 18650 Model - Samsung - componentstree
LG 18650 MJ1 3500mAh (3c) LI-ION BATTERY - Robu.in | Indian Online Store | RC Hobby | Robotics
Buy Original LG 3200mAh 10A 3.7 Volt Li ion Battery at Low Price
Buy Original SAMSUNG 3.7 v Li ion 2500mAh 18650 Battery In India
Buy SAMSUNG 18650 26J 2600mAh Li ion Battery Online | Robu.in
Buy Original LG 2600mAh B4 18650 Lithium Battery In India | Robu.in
Buy Original SAMSUNG 30Q 18650 3000mAh Battery In India
Buy Original LG 2600mAh M26 18650 Lithium Battery In India | Robu.in
Buy Original SONY VTC6 18650 3000mAh Li ion Battery In India | Robu
Buy Original Panasonic NCR18650B 3400mAh Li ion Battery In India
Buy Original Panasonic NCR18650B 3400mAh Li ion Battery In India

As I said in 1st post after watching YouTube comparison I selected LG MJ1 but there are more batteries available compared in this old video. So guidance needed.

xxo
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The 11000 mAh Soshines are the ones. I would not get the tenergy premium as I believe they will self discharge fairly quickly – get the soshines or the tenergy centuras.

nOne
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xxo wrote:
The 11000 mAh Soshines are the ones. I would not get the tenergy premium as I believe they will self discharge fairly quickly - get the soshines or the tenergy centuras.

Thank you for suggestions. I checked all D cell reviews here. And it seems Soshine is a good choice as per reviews.
where to buy soshine or tenergy centura, for India shipping. Above mentioned post (Massive post on where to get lithium-ion batteries everywhere in the world!) does not provide any Asia related site.
https://ru.nkon.nl/ or somewhere else. Shipping and covid19 restriction are important.

 

Need 1 more suggestion for 2032 batteries. Panasonic or Duracell?
https://www.amazon.in/dp/B00LVMTA2A/(link is external)
https://www.amazon.in/dp/B08Y1TQ8K7(link is external)

 

For 18650, as I posted earlier, after watching YouTube comparison I selected LG MJ1 but there are more batteries available compared in this old video. So guidance needed.
I checked battery index (https://lygte-info.dk/info/batteryIndex.html), for max 3A and 3.7v, LG, Samsung are good and available locally as I mentioned sites above post. but no Keeppower locally available.
primary applications will be 3V-5V 3A diy arc generator, arc plasma gas lighter circuit, replacing very old Dell Latitude D530 laptop battery 6 li-ion cell, 11.1V, 56WH (year 2007) (Type M9014)
secondary applications diy power bank and some other stuffs.

Dell Latitude D530 laptop battery 6 li-ion cell, 11.1V, 56WH (year 2007) (Type M9014)

 Batteries with ridiculous ratings - https://lygte-info.dk/info/BatteriesRidiculousRatings%20UK.html

I think I will try 1st high capacity batteries, from below whichever costs lower.
Samsung INR18650-35E 3500mAh (Pink),
Sanyo/Panasonic NCR18650GA 3500mAh (Red),
LG 18650 MJ1 3500mAh (Green)

If they discharge fast then I will try high current + high capacity batteries mentioned there, from below whichever costs lower.
Samsung INR18650-30Q 3000mAh (Pink),
LG 18650 HG2 3000mAh (Brown),
Sony US18650VTC6 3000mAh (Green)

Any suggestions for this?

sneym321
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Speaking of the water heater, can you add a 3v power supply there? There are connectors that can turn off battery line when power supply cable is plugged in. If power is out you unplug the power supply cable and turns on the battery line back.

Edit: I came across AA and D dummy batteries that are wired to a power supply. https://www.aliexpress.com/item/1005001619613398.html

nOne
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sneym321 wrote:
Speaking of the water heater, can you add a 3v power supply there? There are connectors that can turn off battery line when power supply cable is plugged in. If power is out you unplug the power supply cable and turns on the battery line back. Edit: I came across AA and D dummy batteries that are wired to a power supply. https://www.aliexpress.com/item/1005001619613398.html

Late reply. Sorry for the delay.

Replaced Gas Geyser batteries with wired connection 5v 1A charger + 2 meter long USB cable for limiting current. Also added switch board near Geyser for convenience and for safely turning off supply.
When Gas Geyser connected to 18 watt fast charging high speed USB cable used for mobile devices. Sparking was too fast and loud so used normal USB cable 2 meter long. Now everything works fine.
So no D size battery needed and no converter needed now.

I purchased this Power Bank Case from banggood last year.
Tried batteries from old laptop battery mentioned here. It's working great.
C16-PD-QI Removable 16-section Power Bank Shell Mobile Power Bank Assembly Kit Diy18650 Battery Box Wireless&Quick Charging Version - Black
Earlier I faced problem with this power bank as it was showing incorrect percentage. But eventually I learnt that, after inserting batteries you need to completely discharge and charge powerbank once for to see exact percentage.

So, I purchased 20 nos. Samsung INR18650-35E at ₹442.6 (including taxes) from "IndiaMart" to India. As I couldn't find any website which ships to India and shipping cost is too high.
I want to know are these genuine or fake. As I am getting 1800-1900 mAh capacity from battery. Cut-off voltage 3.11 volts as power banks shows 0% and shut down.
I measured capacity using AccuBattery and Battery Guru apps from Google Play store.
Charged power bank to 100% (16*3500 mAh approx = 56000 mAh) then discharged power bank by charging 3 mobiles with these apps installed and measured capacity of total 16 batteries. Result was 29737 mAh Battery Guru app and 30594 mAh on AccuBattery app. So calculated that each battery have around 1800-1900 mAh.
Please check attached images.

Quote:
All weighs exactly 48 gm. (I don't have precise digital weighing machine. It does not measure decimal count.)
Measured voltage value is around 3.68 v to 3.71 v. (Measured with decent multi meter.)
All 20 batteries have same Samsung manufacture date code

J5H9 699A1 (2 lines of code near top according to Mooch YouTube Video)

01. 71C3 B08
02. 71C3 B05
03. 71C3 B03
04. 71C3 B01

05. 74A4 B02

06. 72F9 B06
07. 72F9 B07

08. 71D7 B01
09. 71D7 B05
10. 71D7 B05
11. 71D7 B06
12. 71D7 B08

13. 72B2 B03
14. 72B2 B03
15. 72B2 B04
16. 72B2 B04
17. 72B2 B06

18. 75E8 B01
19. 75E8 B05
20. 75E8 B02

All batteries looks genuine feel genuine.
Some scratches are there on bottom but these are due to bad shipping from the supplier.
No round scratches on bottom usually sign of used batteries.

Only problem with capacity. Don't have any charger, device to measure capacity.

Attached Images:

d_t_a
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nOne, would you happen to have lithium-ion battery charger with capacity test (discharge test) function)?

If I understand correctly, you’re measuring the discharge capacity of the powerbank with these Samsung 35E.

Also, the discharge capacity is with USB 5v (powerbank output, unless it also outputs at USB-QuickCharge, which may be 9v or 12v or some other QuickCharge voltage)

Now, the 18650 batteries are at 4.2v when full charge and around 2.5-3.0v consider as empty.

The powerbank converts the 2.5-4.2v into USB 5.0v (some powerbanks may be slightly higher or slightly lower than 5.0v, like 4.8v-5.2v).

But anyway, your measurement of 29737mAh or 30594mAh (using Android App) would likely be from USB 5v back to the 3.7v (nominal) for lithium-ion battery of the cellphone (also note, these readings are reported by the cellphone’s Android sensor (something like that, based on my limited understanding).

There are a lot of conversions in between (from the Samsung 35E 18650’s 3.7v nominal voltage to USB 5.0v and back to the 3.7/3.8v of cellphone lithium-ion battery).

There is also efficiency losses during powerbank conversion of voltage. As such, I think it’s a bit difficult to determine the correct capacity of your Samsung 35E.

However, we can be pretty sure they are higher than the 1900mAh (if we multiply the conversion factor 5.0v (USB nominal voltage) divided by 3.7v (18650 nominal/average voltage) = 1.35 1900 * 1.35 = 2560mAh (at least), and we haven’t factored losses in conversion, and also battery capacity are usually measured not just down to 3.0v, but usually down to 2.5-2.6v to get the “manufacturer capacity rating”

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Agree with d_t_a, OP is forgetting conversion losses with boost circuits and typically cheap 5v boost circuits are only around 70-80% efficient, some go as high as 95% though.

If this is a USB-C PD or QC circuit with 9v/12v/15v support I can almost guarantee it has low efficiency within the different boost circuits.

You will never see a 1:1 conversion when changing voltages.

nOne
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d_t_a wrote:
nOne, would you happen to have lithium-ion battery charger with capacity test (discharge test) function)? If I understand correctly, you're measuring the discharge capacity of the powerbank with these Samsung 35E. Also, the discharge capacity is with USB 5v (powerbank output, unless it also outputs at USB-QuickCharge, which may be 9v or 12v or some other QuickCharge voltage) Now, the 18650 batteries are at 4.2v when full charge and around 2.5-3.0v consider as empty. The powerbank converts the 2.5-4.2v into USB 5.0v (some powerbanks may be slightly higher or slightly lower than 5.0v, like 4.8v-5.2v). But anyway, your measurement of 29737mAh or 30594mAh (using Android App) would likely be from USB 5v back to the 3.7v (nominal) for lithium-ion battery of the cellphone (also note, these readings are reported by the cellphone's Android sensor (something like that, based on my limited understanding). There are a lot of conversions in between (from the Samsung 35E 18650's 3.7v nominal voltage to USB 5.0v and back to the 3.7/3.8v of cellphone lithium-ion battery). There is also efficiency losses during powerbank conversion of voltage. As such, I think it's a bit difficult to determine the correct capacity of your Samsung 35E. However, we can be pretty sure they are higher than the 1900mAh (if we multiply the conversion factor 5.0v (USB nominal voltage) divided by 3.7v (18650 nominal/average voltage) = 1.35 1900 * 1.35 = 2560mAh (at least), and we haven't factored losses in conversion, and also battery capacity are usually measured not just down to 3.0v, but usually down to 2.5-2.6v to get the "manufacturer capacity rating"

No don't have any charger. Looking to buy one in India as Xtar products are not available, Nitecore UMS2 is only good option from here. https://lightorati.in/nitecore-ums2-usb-quick-charger
But prices are too high in India.

For almost all powerbanks cut off voltage is around 2.99v to 3.11v where it's empty "0%". And around 4.11v to 4.17v is where battery is full "100%"
C16-PD-Qi powerbank have QC3.0 support.
Input - 5V-3A, 9V-2A, 12V-1.5A
Output - 3.4V-5.5V-5A, 4.5V-5A, 5V-4A, 9V-2A, 12V-1.5A,
Wireless Output - 5V-2.1A
So according to all the conversions to 5v or more and all calculations you mentioned, there are efficiency losses.
So from what you said, power banks which provides 10000 mAh battery will have 10000 mAh battery but you will never get all 10000 mAh due to efficiency losses, is this correct?
So, efficiency losses + manufactured in 2017, 40% loss of capacity.
1. Powerbank voltage conversion Loss
2. Cable loss
3. Android Device BMS loss
4. 3rd party Android App Calculation loss
In simple words because of lots of calculation in between it's exact value can't be determined.
And about 2.6v, I have seen this cut off voltage where BMS circuit is not soldered with battery (small li-ion rectangular batteries) like in Arc Lighters.

So only option is to get charger with capacity test.

Thank you so much for the detailed information.

nick779 wrote:
Agree with d_t_a, OP is forgetting conversion losses with boost circuits and typically cheap 5v boost circuits are only around 70-80% efficient, some go as high as 95% though. If this is a USB-C PD or QC circuit with 9v/12v/15v support I can almost guarantee it has low efficiency within the different boost circuits. You will never see a 1:1 conversion when changing voltages.

Okay. So everything is about efficiency.

I was worried about batteries. Because it was my 1st purchase of 18650 batteries. I thought I was looted by this dealer.
Batteries looked genuine and written codes were also genuine, only capacity was something not getting up to mark.

One question is there.
Is it possible to buy batteries which are manufactured in same year? To avoid possible battery losses when not in use?

nick779
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nOne wrote:
only capacity was something not getting up to mark>

You measured wrong. To get an accurate measurement you would need to measure the power extracted from all of the cells before they go through the power bank or measure the cells themself in something like a battery analyzer. You will never receive an accurate measurement from the usb port as it is after all of the conversion circuitry.

nOne
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Joined: 10/22/2021 - 07:47
Posts: 12
Location: India

nick779 wrote:
nOne wrote:
only capacity was something not getting up to mark>
You measured wrong. To get an accurate measurement you would need to measure the power extracted from all of the cells before they go through the power bank or measure the cells themself in something like a battery analyzer. You will never receive an accurate measurement from the usb port as it is after all of the conversion circuitry.

Yes and you all corrected me. Thanks for that.

"To get an accurate measurement you would need to measure the power extracted from all of the cells before they go through the power bank"

^^ I didn't understand please explain.

Looking to buy one in India as Xtar products are not available, Nitecore UMS2 is only good option from here. https://lightorati.in/nitecore-ums2-usb-quick-charger