Knowledge about 18650 Rechargeable Li-Po Battery

Goldmore is very concerned about natural environment issues. We want to give a hand to reduce environment pollution. So, lots of our led lights are powered by Li-Po battery, such as camping lantern, LED flashlights, projector lights, Night lights, LED sensor lights, work lights and so on. Rechargeable Li-Po battery can reduce material consumption and be more friendly to environment.

Do you know Li-Po battery very well? Let me introduce Li-Po battery carefully ranging from differences, characteristic, charging and discharging function and the problems you might be met during using. And then you will know our LED lights better.

Keep reading:


What are the differences between Li-Po battery, Ni-Cd battery and Ni-Mh battery?

Compared with other rechargeable battery, Ni-Cd battery and Ni-Mh battery, the advantage of Li-Po battery is very obvious. Let’s take a look at the diagram and compare the three batteries.

Battery comparation
Battery Comparation

You can see the data in this form. Li-Po battery has higher voltage, bigger capacity, more use times, lower self-discharge. It cannot cause environment pollution. The advantage of Li-Po battery is every obvious.



What Does “18650” Mean in 18650 Li-Po Battery Type?

You may be wondering what we mean by “18650” in 18650 lithium batteries. 18650 battery is one of Li-Po battery. “18” refers to a battery diameter of 18mm; “65” refers to the battery length of 65mm; “0” indicates that the lithium battery is cylindrical.



The Voltage and Capacity of 18650 Battery

18650 Li-Po battery’s nominal voltage is 3.7V; charging voltage is 4.2V, usually capacity value is 1200~3350mAh.

Li-Po battery with different capacity has different size. If you want the product runs longer and you want to change the battery to the battery with bigger capacity, please let us know, in case of the size of battery can not fit into the battery case.



What Advantages Does Li-Po Battery Have?

  • The range of usage is wide. It can power electronic equipment like laptops, instruments, toys, camera, led lights and so on.
  • It can be used in series or parallel.
  • Internal resistance is small, which can reduce the power consumption of the equipment, prolong the power supply time of the equipment. Become the most promising and hopeful  product to replace nickel-metal hydride battery.
  • High Voltage. The voltage is generally 3.7V, 4.2V, much higher than other batteries.
  • High safety performance. The battery equipped with a protective plate can prevent undesirable hidden dangers caused by overcharge and over-discharge of the battery.
  • Long life span. The battery can be recycled more than 500 times in normal use.
  • Huge capacity. When the batteries are connected in series, the capacity can be superimposed.
Breakdown Drawing of Li-Po Battery
Breakdown Drawing of Li-Po Battery

What Kinds of Protection Does Li-Po Battery Equip?

18650 lithium battery generally with short circuit protection, over current protection, over voltage protection, battery reverse connection protection.

  • Overdischarge protection: in order to prevent the overdischarge state of lithium battery, when the lithium battery is low than its discharge voltage detection point, that is, the discharge protection is activated and the discharge is terminated.
  • Overcharge protection: When the charging device overcharges the lithium battery, the charging state shall be terminated in order to prevent the internal pressure from rising due to the temperature rise. Overcurrent or short circuit protection: When the discharge current of lithium-ion battery is too large or short circuit occurs, the protection device will activate the over current protection function



What Kinds of Charging Stage Does Li-Po Battery Have?

Lithium battery charging is divided into two stages:

The first stage is constant current charging, when the battery voltage is lower than 4.2V, the charging device is charged with a constant current.

The second stage is constant voltage charging. When the battery voltage reaches 4.2V, due to the characteristics of the battery, the battery will be damaged if the voltage is too high. The charging equipment will fix the voltage at 4.2V, and the charging current will gradually decrease. When the current decreases to a certain value, it will cut off the charging circuit.


What Problems I Will Meet When I Use Li-Po Battery Powered Products?

  • Battery can not be charged.
  • Battery can not discharge.
  • Battery can not be full charged.
  • Working time is short.
  • Voltage of battery id low.
  • Temperature of battery is too high.
  • Life span of battery is short.
  • Battery stops working during usage.
  • Battery leakage and fire.
  • Battery explosion.

If you meet above problems when you use Li-Po battery powered products, please read on. You will find out the reason.

If you don’t meet these problems yet, also please read on. When you meet these in the future days you will know what happened.


What Causes the Problem of Not Being Charged?

  • The battery charger is faulty & the charger does not match.
  • The charging environment temperature is too low. 18650 battery has low temperature charge and discharge requirements. Cannot be used in low temperature environment for a long time.
  • The charging environment temperature is too high. The 18650 battery generally has a protection mechanism. Diaphragm paper is easy to break when used at high temperature.
  • The charging environment humidity is too high. The 18650 battery is easy to cause circuit failure or short circuit when it is used under high ambient humidity.


Why the Battery Cannot Be Discharged?

  • The battery has no voltage and large internal resistance
  • The battery protection circuit is damaged
  •  Discharge equipment circuit fault
  • Pole lug snapped, causing short circuit


Why the Battery Cannot Be Full Charged?

  • The battery has not been used placed for too long, and the lithium ions enter the dormant state.
  • The battery capacity is lower than normal due to self-discharge.


Why is Working Time of Battery Short?

  • Battery capacity is insufficient.
  • It is used in harsh environment for a long time.
  • The battery is too full or too low (overcharge or over-discharge).
  • Instability of charging voltage and current.


Why is Battery Voltage Low?

  • Short circuit, overcharge, reverse charge (forced overdischarge).
  • Continuous overcharge of high current, expansion of battery core, direct short circuit of positive and negative poles.
  • The burr pierces the diaphragm paper to make the short circuit; Improper placement of positive and negative poles causes short circuit  poles; The positive plate shorted out on touch the steel case.
  • Positive pole lug touches negative plate short circuit; Negative off powder into diaphragm paper; Diaphragm paper damage…..


Why is Temperature of Battery High?

  • Excessive charge/discharge current causes temperature rise (during use).
  • Battery short circuit (positive and negative poles touch together).
  • The power of the equipment is large and the heat dissipation system is poor.
  • Poor operating environment.


Why is Life Span of Battery Short?

  • Long-term overcharge and over-release.
  • The use of poor environment (high temperature, low temperature).
  • Long periods of full or no power.


Why Does the Battery Stop Working During Using?

Electromagnetic internal movement of battery is damaged.


Why Does Battery Leak Liquid and Get Fire?

  • When welding the battery shell and cap, the welder is not stable.
  •  When the steel ball is sealed, the size of the steel ball is not appropriate.
  •  The positive electrode of the cap is not tight when riveting, and there is a gap.
  • The instrument is not original, and the input and output do not match.
  • Often knock against in the process of use, damage the aluminum plastic film.
  • Abnormal overcharge and overdischarge way.


Why Does Battery Explode?

  •  The battery temperature is higher than 140℃, causing explosion.
  • Overcharging leads to thermal runaway.
  • The binder drops powder to form burrs to Pierce the diaphragm.
  • The electrolyte produces water by biochemical reaction under certain conditions.
  • The cleanliness and dryness of the winding process are not enough.
  • A short circuit.


What Information is Marked on the Surface of the Battery?

Battery anode and cathode, company registered trademark, battery product model, product capacity code, production month code, factory code, product batch date code, company code, product production year code and flow code.


For any questions or inquiry, contact GoldMore sales team.

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