LG HG2 Battery Review 18650 Test 20A 3000mAh Part 1

Let's start with LG HG2 battery review - performance test.

LG 18650HG2 18650 battery li-ion (lithium-ion) is made and distributed by well-known LG Chem manufacturer located in South Korea.
LG Chem is also known as LG Chemical, the largest chemical company in S. Korea.
Quick Fact:The Ford Focus Electric, Volvo V60 & Chevrolet Volt are powered by LG batteries.

Basic info

Specifications:

• Model: INR18650HG2
• Capacity: 3000mAh
• Released: 2014
• Product Classification: Cylindrical rechargeable lithium ion battery
• Intended use (application): Power Tools
• Max. Constant Current 20 A (20000 mA)
• Cycle Life @ 10A: 300 cycles at 10 A
• Cycle Life @ 20A: 200 cycles at 20 A
• Initial AC impedance: less (or equal) than 20 mΩ
• Dimensions: Diameter Max 18.5mm, Height Max 65.2mm
• Weight: Max 47g
• Operating temperature (battery cell surface temp.): -20 ~ 75 ℃
• Lower limit (cutoff) discharge voltage under load: 2.5V

Yes, that is correct this cell is made for Power Tools.
Unprotected 18650 batteries are not intended to be used in vape mod (e-cig) devices, or flashlights.
Why?
That is because each 18650 battery (or battery pack) should have properly designed and installed electronic protection circuit (per manufacturer recommendation). Incidentally, LG HG2 became one of the most popular 18650 vape battery cell. That is one of the reasons I picked this particular battery for this review & test.

LG HG2 18650

Manufacturer datasheet 

For this testing, I will use lab calibrated CBA IV Pro Battery Tester - Computerized Battery Analyzer. 
Calibrated and tested to accuracy levels of < 1% Amp load, < 0.5% volts

Review-Test 1 : Capacity @ 15A Continuous Discharge INR18650HG2

Voltage vs Capacity: Let's see how much capacity we can get from LG HG2 under 15 Amp constant (continuous) discharge load. The test battery is fully charged to 4.2V, and discharged to 2.5V. Click on the picture below to see full-size battery discharge graph with the (green) capacity curve.

15A continuous discharge is somewhere in between two max. discharge values provided by manufacturer-LG for this 18650 li-ion battery cell. 
10A for approximately 300 cycles, and 20A for approximately 200 cycles.
LG HG2 total capacity under 15A is 2835mAh which is very good for this type of battery under 15 Amp continuous discharge rate. 

Voltage drop/sag

The green line in the graph above visually represents what is happening with the battery voltage once power button on your device is pressed.
It is called Voltage Drop.
Voltage drop value greatly depends on:

• Discharge Load. For this part of the test, it is: 15A Continuous high current drain
• Internal battery resistance 

18650 Li-ion batteries (all lithium based batteries) have different internal resistance values. Internal resistance depends on build quality (quality control), design (internal, and external), chemistry modifications, a number of cycles, and age of battery cell.

Review-Test 1 : Time vs. Battery Voltage @ 15A Continuous Discharge INR18650HG2

This is the interactive chart. Hover mouse pointer over green line to see it in action.

LG HG2 
Discharged from 4.19V to 2.5V @ 15A continuous load in 11 min. and 28 sec.

Review-Test 2 : Capacity @ 20A Continuous Discharge INR18650HG2

LG HG2 Amp limit (according to official manufacturer datasheet) is 20A Continuous current load.
Let's see how this high drain battery can handle 20 Amp

Click on the picture below to expand discharge graph with the capacity curve:

20 Amp continuous discharge graph

This battery can handle 20 Amp of continuous discharge without problems, but the question is: should you use LG INR18650HG2 @ 20A?
In my opinion, you should not run it at 20 Amp too often.
Why you should not run 18650 battery at full (max) amp load (limit)?
If you read manufacturer datasheet carefully you will see that discharging this li-ion 18650 battery with the very high load will drastically reduce the total number of charge/discharge cycles (lifespan).

Is it good for LED Flashlight?

Luckily LED Flashlights (even high-power 2016 models) do not require such a high current to work at the full power level (e.g. turbo mode).
I will test this (officially rated by LG) 3000mAh battery at lower currents (more suitable for flashlights) just to see how it behaves (voltage drop should not be as deep as @ 20A, and 15A discharge) under lower currents. I think we will be able to get more usable capacity out of it at lower loads. Scroll down to see the test at 5A load.

Is it good for vape mod (electronic cigarette)?

Some new, and inexperienced battery testers are trying to rate li-ion batteries for vape mod users based on continuous discharge tests, and temperature only.
This is definitely the wrong way to test, and recommend (not recommend) batteries for vaping devices.
Lack of experience and basic knowledge about li-ion technology is the biggest problem in the vaping community.

When we want to test 18650 li-ion battery for vape devices - pulse test is the only way to do it. Pulse discharge test is very close to what is really happening with battery cell when it is inside your box mod, or any e-cig device (mech mod, etc.).
I will perform pulse (burst) tests as well, stay tuned.

Using only battery temperature level to rate li-ion battery for vape mods is wrong and provides false (inaccurate) ratings:

•  Battery temperature level during continuous discharge process is completely different from pulse discharging temperature. 
• Measuring temperature and rating li-ion battery based on continuous current discharge have nothing to do with vapers. Or in simple words: it gives you wrong information about (real) battery capabilities.

 If battery tester provides ratings based only on temperature then always ask for full temperature graph to be revealed (alongside discharge curve).

Why?

Because, a temperature of that battery after 0.5 to 2 minutes under high current load, is much lower than temperature after 4 to 5 minutes under that same high current load.


Advice for vapers:
If you see battery tests ratings based on temperature, and temperature graph (curve showing temperature progress) is hidden, then something is wrong with that test data.
Always ask: Why temperature graph is hidden?
I will provide more tests with temperature data included. These are just basic continuous discharge tests - to see how this cell can handle various constant current loads. So far so good.

Review-Test 3 : Capacity @ 5A Continuous Discharge INR18650-HG2

Let's continue with LG HG2 review. This part of the test will be dedicated to continuous discharge at 5A (5000mA) constant current. From fully charged 18650 battery (full charge = 4.2V)] to the lowest voltage level we can go with this particular li-ion cell -  which is 2.5V.
Click on discharge graph below to expand image - full size.

5 Amp constant current load test discharge capacity graph

Review-Test 4 : Battery Temperature @ 10A Continuous Discharge LG 18650HG2

This is very interesting, and useful interactive chart - hover your mouse over red line (temperature), or blue line (voltage), and you will be able to see:

• Battery temperature - red
• Battery Voltage - blue
• Time (in seconds)
• Current load is 10A constant value

Remember:
There is no 18650 30A 3000mAh battery in existence
There is no 35A or 40A 2100mAh or 2600mAh 18650 battery in existence
There is no 20A 3100mAh or 3200mAh or 3500mAh 18650 battery in existence


Safety is the only reason I am doing this.
Li-ion battery can be very dangerous when fake rating and bad seller/tester meet together.


To be continued...