Because my own dental cleaning device uses an ordinary battery, I feel that there is insufficient power, so I would like to buy a few rechargeable batteries to use it. Before I saw Aunt Zhang on the battery, BYD seems to be good, and it is much cheaper than Ipod.
BYD's battery and charger Taobao almost Tmall flagship store in the sale, and home delivery
There is a big "BYD" logo and some basic information on the front
A seal on the box ensures the quality of the battery delivered to the user
The battery has a plastic cover. If you want to use it, you must tear off the packaging.
The charger is a plastic bag, not a disposable plastic seal like a battery.
The entire design of the charger is portable, using a folding plug design, and the battery compartment also has a plastic cover protection 
The plastic cover is not covered in its entirety, and there is a gap on the side
Note: The BYD logo is not a sticker. It seems to be inlaid. I don't know what it is.
The charger's work is still good
The voltage of the battery is 1.2V, the power is 2000mAh, and it can be recharged over 1000 cycles, and 70% of the electricity is still stored after one year (Official data)
Can charge up to four AA batteries or two AAA batteries at the same time
Some simple parameters on the back of some chargers
The battery's packaging is printed with precautions
It can be seen that the head of each battery has four air holes
From the instructions it is known that this charger is capable of charging nickel-metal hydride batteries and nickel-cadmium batteries and has a trickle charge function. Chargers at this price point are relatively rare.
The maximum charge current for AA batteries is 700mA, the maximum charge current for AAA batteries is 350mA, and the trickle charge current is 80mA
This charger is able to identify new batteries (only tried BYD's own, other do not know), put the new battery, the LED light will flash twice after the light, the first use of about 6 hours to put a new battery Full (two sections), full backlight will go out
Say the advantages:
It supports a wide voltage of 100-240V, which means that the global unimpeded, but now most electronic products have this feature
With trickle charge function, the battery can be charged to saturation power state
Folding plug design, easy to carry
The price is cheap, the price of the battery is only a little more than half of the similar specifications
Features
â—† Designed For Water and Dust Tight(IP67)
â—† Small Compact Sizeâ—† UL&ENEC&CQC Safety Approvals
â—† Long life & high reliability
â—† Variety of Levers
â—† Wide Range of wiring Terminals
â—† Wide used in Automotive Electronics,Appliance and Industrial Control etc.
â—† Customized Designs
Ip67 Micro Switch,Micro Push Switch,Ip67 Sealed Micro Switch,Waterproof Micro Limit Switch
Ningbo Jialin Electronics Co.,Ltd , https://www.donghai-switch.com