Xero 18650 Test ( 3500mAh )

5 posts / 0 new
Last post
old4570
Offline
Last seen: 1 day 19 hours ago
Joined: 09/06/2010 - 02:44
Posts: 3227
Location: Land of Oz
Xero 18650 Test ( 3500mAh )

I was able to borrow some Xero 18650 3500mAh batteries for a quick test ( Capacity ) .
As delivered the resting voltage on all cells was 3.48v ( Perhaps a little on the low side )
I put all 8 batteries through my charger and they all came out ( after resting ) @ 4.15v

My initial discharge test was @ 1Amp .
With a resting voltage of 4.15v the battery voltage under load ( 1A ) quickly dropped to 3.8v and about 5 minutes latter was at 3.75v . ( Under load )
This initial discharge returned some 2779mA discharged to 3volts .. ( Not really close to 3500mA )

My second discharge was at 0.5A
This time I put the battery in a older Xtar Charger to try an top it up ( 2 batteries ) and the power supply for the charger died .
Well , I had another Xtar charger with a larger power supply so I borrowed the PS from that and topped up the batteries ..
One came of ( after resting ) at 4.19v and the other was 4.17v ..
So taking the 4.19v battery :
At 0.5A discharge the battery sagged ( under load ) to 4.02v
Discharging to 3v returned 2937mA , still quite shy of the 3500mA printed on the label .
I get the feeling the batteries are discharged to 2.5v to make the claimed capacity .. ( I will do a quick search )

From the seller :

Capacity (Ah): 3.5 Ah Max (3500 mAh) Min (3350 mAh)
Nominal Voltage (V): 3.6 ~ 3.7 V
Charging Voltage (V): 4.2 V
Charging Current (Ah): 1.47 Ah (1470 mAh)
Cut-off Voltage (V): 2.5 V
Energy (Wh): 12.5 Wh
Energy Density (Wh/L): 745 Wh/L
Max. Discharge rate ©: C Rating 2.5C (Recommended Max current 10 Amp)
Pulse current (Ah): (5-6 sec.): 15 Ah
Weight (g): 48 g (+/- 0.5 g)
Diameter (mm): 18.6 mm (+/- 0.03 mm)
Height (mm): 68.5 mm (+/- 0.3 mm)
Protected: YES (Seiko MOS-FET)
Top (positive side): Nipple top
Model: XERO 18650 GAP (NCR18650GA Cell)
Assembled for XERO PTY LTD Australia (Cell & PCB MOS-FET Made in Japan)

Yeah , 2.5v is the cut of voltage ..
A lot of devices will cut off before that ( depending on application ) , especially if safety is of concern ( RC transmitters for example ) .
Do most flashlights (1 × 18650) turn off @ 3v , probably .
These are not my batteries so my testing ends here ..

 Always remember , the easiest thing in the world to do , is to expel hot air from your lungs and through some vocal chords ..
The resulting sound may , or may not be worth listening too ….

 

MRsDNF
MRsDNF's picture
Offline
Last seen: 10 hours 44 min ago
Joined: 12/22/2011 - 21:18
Posts: 11690
Location: A light beam away from the missus in the land of Aus.

Thanks for the review.

This must be the company here.

http://www.ebay.com.au/itm/2x-XERO-Protected-Panasonic-18650GA-3500mAh-L...

My current and or voltage measurements are only relevent to anything that I measure.

Budget light hobby proudly sponsored by my Mastercard and unknowingly paid for by a hard working wife. 

djozz said "it came with chinese lettering that is chinese to me".

old4570 said "I'm not an expert , so don't suffer from any such technical restrictions".

Old-Lumens. Highly admired and cherished member of Budget Light Forum. 11.5.2011 - 20.12.16. RIP.

 

stephenk
stephenk's picture
Offline
Last seen: 44 min 47 sec ago
Joined: 01/30/2016 - 05:09
Posts: 1168
Location: Australia

Is this a new Aussie brand? I’ll stick to supersports600 Blazar protected cells which I’ve been very happy with.

snakebite
snakebite's picture
Offline
Last seen: 9 hours 42 min ago
Joined: 11/20/2013 - 20:21
Posts: 1649
Location: dayton oh

iirc ga are rated to 2.5v.
sag may be a crummy protection board.

old4570
Offline
Last seen: 1 day 19 hours ago
Joined: 09/06/2010 - 02:44
Posts: 3227
Location: Land of Oz

http://www.ebay.com.au/itm/2x-XERO-Protected-Panasonic-18650GA-3500mAh-L...

Looks like them , ……

Voltage sag under load = All batteries voltage sag under load …
Which is why discharging at high current for capacity is a mistake ( due to the voltage sag under load ) , the greater the load the greater the sag , the less accurate the result ( For Capacity )

Lots of battery theory out there ! I personally would not discharge past 3.5v or 3.6v and will quite happily throw a battery in the charger @ 3.8v or there about . ( Higher )

 Always remember , the easiest thing in the world to do , is to expel hot air from your lungs and through some vocal chords ..
The resulting sound may , or may not be worth listening too ….