How to tell difference between NonePotective and Protective 18650 Rechargeable Battery

Have you ever bought 18650 rechargeable Li-ion battery? How is the quality?Do you know how to find qulified 18650 battery?Today,we will talk about this case here.

Here are two similar looking 18650 rechargeable battery which is used for super bright led flashlight.Firstly,pls mark which one you think is better.Then go ahead reading.Let's us check whether your're right.

                                                                    Battery A:

Battery B:

Now let's start to find right answer.Normally speaking,18650 battery with protective circuits board is better than without.You may ask why?Here are 3 points for why

Point 1:Protect your battery from over discharging.Some high brightness led flashlight does not have automatically cut off power function under low voltage.So if continue lighting,it may cause inside battery low voltage called "over discharging".If with protective circuit board,battery will stop work under this situation.If without,battery life will end and never work any more.

Point 2:Prevent your battery to over charging.Generally speaking,Max.voltage of 18650 battery is 4.2V.If long time charging,voltage will be higher than 4.2V,which will shorten battery spantime(For example:USB device voltage is 5V,if we use that kind device to charge none protective 18650 battery,which is very dangerous and shorten battery spantime.

Point 3: More safety

What protective circuits board looks like?Here are photos for your reference.

Where is protective circuits board normally?Following photo will tell you

Yes,the bottom of battery.Compared with normal 18650 battery,protective version comes with circuits board at bottom,which could be found directly by viewing.This also makes it 2-3mm longer than normal nonprotective 18650 rechargeable battery,like below photos.

So,now could you find which one is qualified?Yes,it is Battery A.

If you have 18650 battery in hand,go back home and check whether yours has circuits board with what you learned today.If without circuits board,pls pay attention during using.NEVER make it overdischarging.If your flashlight becomes dim,pls take out your battery immediately and charge it.Pls use protective charger for charging cause this kind charger also could prevent overcharging.