Classifications of Batteries

The range of different types of batteries has widely expanded in the last few years. As a reliable battery manufacturer, we are perfectly aware of your needs and try to meet all your expectations. Here we are going to examine the batteries from all sides—longevity, energy density, load characteristics, self-discharge, maintenance rules and operational costs. 
1. Lithium batteries can be roughly classified into two types: Lithium metal batteries and Lithium-ion batteries, while the latter one doesn’t contain metallic lithium and is chargeable. 
Lithium-ion batteries currently have two types: liquid lithium-ion battery (LIB) and polymer lithium-ion batteries (PLB). A lithium-ion battery is a type of rechargeable battery in which lithium ions move from the negative electrode to the positive electrode during discharge, and back when charging. LIB is featured with high working voltage, small size, light weight, high energy density, no “memory effect”, environmentally friendly, low self-discharge rate, long cycling life, thus becomes the ideal energy carrier in the 21st century development.
1. High energy density — ability for higher capacities, already up to 460-600Wh/kg, about 6-7 times in comparison with Lead acid battery;
2. Long cycling life — cycling life can reach more than 6 years, batteries 1C (100% DOD) has the record of charging/recharging and cycling for 10,000 times with LiFePO4 as its anode; 
3. High rated voltage (Monomer working voltage is 3.7V or 3.2V), approximately equals to the voltage serially connected by 3 Nickel Cadmium (NiCd) or Nickel-Metal Hydride (NiMH) rechargeable batteries, and is easy to form battery power unit. Lithium-ion batteries can adjust its voltage to 3.0V by a new type of Lithium battery voltage regulator technology, in order to suit the requirement of small electrical appliances;
4. High power endurance — among which the LiFePO4 batteries (for electric vehicles use) can be up to 15-30C charging/recharging capacity, and is convenient for high-strength startup acceleration;
5. Low self-discharge — one of the most outstanding advantages for Lithium-ion batteries, the rate of self-discharge is less than 1% per month, and is 1/20 lower than NiMH;
6. Light weight — approximately 1/6-1/5 weight of the VRLA with the same dimension;
7. efficiency at both high and low temperatures—can be workable under the environment of -20℃— 60℃, and possible to be used under -45℃environment if went through processing treatments;
8. Environmentally friendly — don’t contain nor produce any toxic heavy metallic pollutions like Pb/Hg/Cad during manufacturing, use or expiring;
9. Basically not consume water during producing, which is advantageous to the water-deficient countries like China.
1. All lithium galvanic batteries has a poor safety performance, and poses the safety hazards to explosion;
2. Li-CO2 batteries CANNOT recharge in large voltage volume, with the high price and poor safety performance;
3. All lithium batteries needs protection circuit to avoid overcharge / deep discharge and shortcuts;
4. Require high-level production conditions and thus with high cost; 
5. Limited use conditions and has the safety hazards in high and low temperature use.  

2. Nickel Cadmium (NiCd) batteries is a type of rechargeable battery with the characteristics of high discharge level, long life and economical price. Nevertheless, it has become out of date nowadays, due to the fact that it includes toxic metals such as cadmium, so it’s environmentally unfriendly and must be recycled or disposed of in the proper way. 
Besides, NiCd batteries also weigh heavy and have “memory effect”, which can decrease your battery's life span, even make it useless. “Memory effect” is, to be specifical, when you recharge a NiCd battery that hasn’t been totally discharged, it “memorizes” the previous charge level and thus the maximum capacity becomes equal to this level. In order to avoid it, you should fully discharge the battery and fully recharge it again at least once in a few weeks.
1. Fast and easy charge — even after long-time storing.
2. Large number of charge / discharge cycles — if thoroughly maintained, the Ni-Cd guarantees over 1,000 charge / discharge cycles.
3. Excellent load performance — the NiCd permits recharging at low temperatures.
4. Long shelf life.
5. The lowest cost.
6. Available in various types and sizes.
1. Comparatively low energy density.
2. “Memory effect”.
3. Environmentally unfriendly.
4. Comparatively high self-discharge — requires recharging after storage.
3. Nickel-Metal Hydride (NiMH) battery is less influenced by the “memory effect” and is easier in maintenance. Nevertheless, it has problems at very low or high temperatures. Although it doesn’t contain heavy metals, it can’t be completely recycled. NiMH battery is notable for higher energy density in comparison with NiCds. It means that you get increased runtime from the battery without extra weight.
1. Easy storage. 
2. Environmentally friendly. 
3. 30-40% higher capacity than in a usual NiCd. 
4. Less evident “memory effect” than in NiCd. 
5. Periodical full discharge/charge cycles are needed less often than NiCd.
1. Limited lifetime — if frequently deep cycled, particularly at high load currents, the operation starts to worsen after 200 to 300 cycles.
2. Limited discharge current — though a NiMH battery can deliver high discharge currents, periodic discharges with high currents decrease the battery’s life span.
3. The NiMH produces more heat during charge and needs a longer charge time compared to the Ni-Cd. 
4. High self-discharge — the NiMH has about 50% higher self-discharge in comparison with the Ni-Cd. 
5. Operation deteriorates if stored at high temperatures — the NiMH should be kept in a cool place and at the condition of charge of about 40%.
6. High maintenance — battery should be fully discharged regularly to avoid crystalline formation. 

General Battery Care

Proper battery storage has many advantages. It prolongs the battery life, and keeps them from becoming hazardous. If you want to store batteries in the right way, you need to follow these easy rules:
1. Store batteries in the original package or boxes exclusive for battery storage. Storing batteries encapsulated in their package assures that they remain protected from environmental impacts such as humidity. It also guarantees that you don’t mix up new, completely charged batteries with old ones, and it prevents their terminals from contacting with other metals.
2. Keep batteries in a cool, dry place. When you select a place to keep your batteries, make certain it’s not exposed to humidity or extreme temperatures, as these conditions can deteriorate the batteries. It will be nice if you store them at around 60°F (15°C), but keeping them at a little higher temperature will also suit.
3. Keep rechargeable batteries at a 40% charge. Rechargeable batteries with nickel or lithium chemistry should be stored at around 40% charge level. This minimizes degradation caused by aging.
4. Avoid contacting of negative and positive terminals of two batteries. If negative and positive terminals of different batteries are contacting, they may conduct electricity and the batteries will be discharged.
5. Leave plastic caps on your batteries' terminals when you don’t use them. Certain batteries, among them many 9V batteries, have a plastic cap fitted over the terminals. You need to leave these caps on during storing to prevent the batteries from losing their charge and conducting electricity.
6. Remove batteries from rarely applied electronics between usages. If batteries remain in electronic devices, they discharge faster.
7. Never keep your batteries in the freezer since this decreases their ability to charge completely.

There can be no doubt that the best instruction for storing is to consult the producers' specifications and recommendations. But there are also some general hints for storing different types of batteries:
Lithium-Ion: The temperature range is -20°C to 60°C but for durational storing period 0°C to 25°C is advised and 15°C is ideal. Batteries should be kept with an incomplete charge (30%-50%).  
Nickel Cadmium batteries: Prolonged storing for Nickel Cadmium batteries doesn’t require the battery in a charged condition, but the battery should be discharged to the final voltage of discharge (with the warning light flashing), then to be stored in the original package or wrapped up with clothing/paper, and kept in a clean, cool, dry place. 
Nickel Metal Hydride batteries should be kept at 40% charge level. As NiMH batteries are notable for a higher self-discharge rate, they will lose more charge during storing and will most likely demand charging before they can be used again. 
Remember, the conditions of storage depend on the active chemicals utilized in the batteries. During storing, the batteries are liable to self-discharge and decomposition of the chemical contents.
Following our prompts you can significantly increase the efficiency of your batteries and enjoy their operation for a long time!