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John WilliamsonHTC SENSATION + SENSATION XE AFTERMARKET BATTERY TEST
 

THERE ARE MANY BATTERIES AVAILABLE SUCH AS THE ANKER 1900 MAH, GOLD 2430 & 2540 MAH, AVAILABLE TO REPLACE THE PUNY STOCK 1520 MAH BATTERY. SOLD ON EBAY, PHONE SHOPS, ETC.

WHICH ARE BEST? DO THEY REALLY HAVE THEIR CLAIMED BIGGER CAPACITIES AND LONGER RUN TIMES?


Its impossible to use a built in "battery meter app, to do this accurately for a bunch of reasons. .

And also impossible to judge just by comparing by "seat of pants". Things like temperature, signal strength, as you move about, network traffic, usage patterns all drastically affect the results.

The only real completely accurate way to test a batteries capacity is to fully charge it (no not with a phone charger! But with a computerised device) and then fully discharge it via computerised controlled discharge test gear. All logged and graphed.

And I have one sat on my bench. Accurate to several decimal places under exact controlled conditions...

So what's the verdict?

 

 
 

 

TEST METHOD

a) fully charge. Phone chargers, or the phone itself cannot do this consistently as they do not all charge to the correct exact 4.200v, and even if they do, they "cut off" at low current before charge is totally complete and this allows the voltage to drop by a small amount later.

Some chargers never turn off, and hold the battery at 4.200 volts indefinitely. So the length of time left on the charger AFTER it has charged effects the amount of total charge held by a small margin. So I charge at CC/CV of 4.2v @ 1000mA for 4 hours each battery, via the Hyperion charger. And I cycled each new battery 4 times before each test for consistency. There was actually almost no change in mAh in, or out, each time on any of these batteries.

b) discharged at 22c at 1000mA for as long as it takes to reach 3.000 volts, at which point the battery is 99.9 percent discharged. And the lowest it should be taken without damage. They instantly bounce back to 3.3v after test load ends. 100Ma is quite a severe discharge rate, but since Lithium's don't suffer from the Peukert effect will not affect the capacity measured.

c) discharged in 50 second pulses with 10 second breaks, to read ACTUAL open circuit voltage off load. And to allow resistance calculation and graphing.

d) all data logged (and controlled) by PC using Hyperion's excellent charger/tester and PC software.

e) Resistance is read and averaged over the whole discharge cycle sampled every 60 seconds. LOW is better!

 

RESULTS

 

Battery 0 - OEM Stock Sensation 1520 mAh Claimed (7 days old)
159 mOhm measured DC Resistance.
Capacity actual measured: 1417 mAh


 

Battery 1 - Chinese (eBay), 2430 mAh gold "Business Battery" (New)
117 mOhm measured DC Resistance.
Capacity actual measured: 1661 mAh


 

Battery 2 - Anker 1900 mAh (New)
137 mOhm measured DC Resistance.
Capacity actual measured: 1631 mAh


 
 
 

HOW I TEST

Cheap eBay wall charger, needed so I could add some connectors to the battery without actually soldering or cutting them open...

Like this, with internal circuitry removed.

To allow connection to a real charger/testing machine...

Testing the OEM battery. This one doesn't do what it says on the tin either. But only lies a little!

 


 

 

 

 

 

 

 

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