In order to your safety when you use Li-ion rechargeable battery, pls note some advices as following.

How to choose a safe Li-ion rechargeable battery?

A.    The safe Li-ion rechargeable battery must have control board inside.
B.    You can find a battery’s safety certificate on the battery, i.e. PSE
C.    The battery has many kinds itself protections

a.    Overcharged protection
b.    Discharged protection
c.    Short-circuit protection
d.    High/Low temperature protection

Overheated or overcharged Li-ion batteries may suffer thermal runaway and cell rupture, and in extreme cases this can lead to combustion. Deep discharge may short-circuit the cell, in which case recharging would be unsafe. To reduce these risks, Lithium-ion battery packs contain fail-safe circuit that shuts down the battery when its voltage is outside the safe range of 3–4.2 V per cell. When stored for long periods the small current draw of the protection circuitry itself may drain the battery below its shut down voltage; normal chargers are then ineffective. Many types of lithium-ion cell cannot be charged safely below 0°C.

Other safety features are required in each cell:

•    shut-down separator (for over temperature)
•    tear-away tab (for internal pressure)
•    vent (pressure relief)
•    thermal interrupt (over current/overcharging)

These safety features increase costs compared to nickel metal hydride batteries, but for your own or your consumers’ safety, these safety features are necessary.

Those very cheap lithium-ion batteries and products using them on the market tend to catch fire when being used or charged.  More and more accidents of this kind, geomangear as one of the recent examples, have happened and thus drew governments’ attention to regulate the rechargeable battery.

Product manufacturers and their following distributors/dealers should not pursue excess cost-down at the cost of end-users’ safety and property.