Product selection guide

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Considerations for constituting the circuit with the Lithium battery

For safe use of the Lithium Battery, please keep follow subjects when you constitute a machine.

Select the proper battery for the use condition.

Each battery has the optimized use current or maximum use current (depends on the environmental temperature, use time). Select the proper battery for each machine’s use condition. If you select improper battery, the over current could cause the heat generation or you may not get an expecting performance

When you use the Battery Array (serial or parallel connection), please keep following cautions
  • The battery array should be used one at a time, do not use multiple one at a same time.
  • Unit battery should be used maximum 3 at a time. If you would like to use more than 3 batteries, have to connect parallel with diodes.
  • When you use the parallel one, connect serial with diodes for each battery.
    Caution: To prevent the short-circuit accident, diode breakage caused by excessive current, 
	please constitute the protection circuit with a fuse or resistor.
  • If you need to use multiple batteries at a time, please use the same type of battery (if possible, use same company products) and do not mix the different type or size of the battery.

    If you use the different type of battery at a time, the performance difference between batteries (of different size, etc) could make the low-performance battery to discharge excessively and could cause a risk of heat generation, breakage, firing. And, if you use battery in parallel without diodes, the low performance battery could be charged and be a reason of heat generation, breakage or firing.
For batteries, use the independent power supply circuit.

If you constitute the parallel use circuit with the different type of battery and alternating current power supply like 2 power supply, 3 power supply circuit, please use independent circuit and make not to compulsory discharge or charge to other power sources.
If the battery would be charged by other power sources, there could be a risk of heat generation, breakage or firing

Constitute a over current protection circuit

Please constitute a battery protection circuit with proper fuse, resistor, PTC device, etc to protect battery from the over current when the machine circuit would be broken. If the current flow the battery excessively when the machine’s circuit is broken, the heat generation, breakage or firing could be happened.

When you use the Lithium Battery as a supplementary power supply (for memory back-up, etc)

Constitute the independent circuit

Not to compulsory discharge or charge by a main power supply, if possible, please constitute an independent circuit with the battery.
If the battery would be compulsory discharged or charged, there could be a risk of heat generation, breakage or firing

To connect with the main power supply circuit, please keep the following subjects.

If you use the home AC power and other DC power supply at a same time, ther is a possibility of charging by a mian power supply, must constitute a protection circuit with diodes and resistors.(UL certification circuit condition) When you constitute a protection circuit, use a diode with a low reverse current and deign a circuit that the charging current by a reverse current should be less than 2% of the nominal capacity.
	If the battery be charged, there colud be a risk of heat generation, breakage and firing.

The structure of the Battery Housing

To design a battery holder and housing, please keep following subjects for a safety.
  • The housing must have a structure of preventing the reverse insertion of the positive and negative terminal. Especially, when you use multiple batteries at the same time, give attention to the insertion direction. Make a inerasable note on the holder of the battery’s insertion direction (+,- polarity and connector’s polarity). When you use the unit battery or multiple batteries at the same time and if you made a reverse insertion with the battery’s + and – terminal, then the battery could be charged and cause the heat generation, breakage or firing.
  • Please make a structure of preventing the mix of different size or type of battery.
  • The battery housing should be designed with the structure of discharging the gas. If the battery housing has a sealed structure and the gas would be generated, the battery housing could be destroyed by an inner pressure rising.
  • The battery housing should have a waterproof structure. If the water would be intruded into the battery housing, the inner pressure and temperature could be rose by the electrolysis and the housing could be destroyed.
  • If the battery housing has a hard structure, please add the blast-resistance function to prevent the total breakage of machine.
  • If the machine has a heat source, the battery housing should be located in the safe place or has a protection structure.
  • The battery room should have a structure of preventing the grabbing and swallowing of the battery by a child.

Notices for Grounding and Terminal

Pay attention to the material and type of contact to secure the electric contact sufficiently.

The improper type of contact or terminal may cause heat by poor contact or unexpected short circuiting.

Pay attention to avoid the electric contact with other areas except for the contact point.
The structure of contact is the battery structure and must not be installed reversely by using the difference of type of +/- terminal.
Never conduct the soldering directly to the terminal of the battery.

If the direct soldering to the battery is conducted, the insulation materials of battery shall be damaged by the heat which leads to the short circuit and if the lithium is melted by the heat, the short circuit may occur inside the battery which may cause fire or explosions.

Description contents

The following contents should be described to providing proper instructions of the Lithium Battery for end users



Battery type (Part name, mark, voltage, etc)

Inner housing , cover

Battery polarity (positive or negative)

Inner housing

Insertion direction of the positive and negative terminal

Inner housing, cover

Do NOT mix the different type of batteries

Around the housing

Must seal the positive and negative terminals with the insulation tape when disuse the battery

Housing neighborhood