Basetech BTL-7, 2-Slot Universal Battery Charger NiCd, NiMH, Li-ion 97009C15 Data Sheet

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In addition a USB charging output (3) via which the USB supplied devices can be operated or 

charged is located at the charger. The USB output can be charged up to a maximum of 2100 

mA and is available with full charging current during power supply operation.
The battery charging slots always have priority 2 and the charging current is limited and de-

activated according to the USB current consumption. The following table shows the available 

output currents.

0 mA

2 x 1000 mA

<1000 mA

2 x 500 mA or 1 x 1000 mA

>1000 - 2100 mA

0 mA

If the charger is connected to a standard USB port (max 500 mA) on the computer the available 

charging current is reduced to 250 mA. The charging slots have priority 2 during this operation. 

The following tables show the available output currents.

0 mA

Max. 250 mA

500 mA

0 mA

  Do not dispose of electric and electronic devices in the household waste!

 

 At the end of its service life, dispose of the product in accordance with applicable 

regulatory guidelines.

You as the end user are required by law (Battery Ordinance) to return all used batteries/re-

chargeable batteries. Disposing of them in the household waste is prohibited.

 

 Contaminated batteries/rechargeable batteries are labeled with this symbol to in-

dicate that disposal in the domestic waste is forbidden. The designations for the 

heavy metals involved are: Cd=Cadmium, Hg=mercury, Pb=lead(designation on 

the batteries e.g. under the refuse bin symbol depicted on the left).

Used (rechargeable) batteries can be returned to collection points in your municipality, our 

stores or wherever (rechargeable) batteries are sold.
You thus fulfill your statutory obligations and contribute to the protection of the environment.

Operating voltage .................................100 – 240 V/AC, 50/60 Hz
Power consumption ..............................max. 0.26 A
Output voltage ......................................5 V/DC 
Output current .......................................max. 2100 mA
Output ................................................... USB

Operating voltage .................................5 V/DC
Input......................................................Micro USB
Output ...................................................2 x charging slots, independent

..............................................................

1 x USB

Charging slot power output ...................max. 7.4 VA
Output Li-Ion .........................................2 x 3.7 V/DC, 1000 mA
Output Ni-Cd/Ni-MH .............................2 x 1.4 V/DC, 1000 mA
Battery types .........................................Ni-Cd, Ni-MH (AA, AAA)

..............................................................

Li-Ion (14500, 18500, 18650, 17670, 

..............................................................

17500, 16650, 22650)

Output current USB ..............................5 V/DC (±10%)
Output current USB ..............................max. 2100 mA 

 

USB cable length ..................................approx. 60 cm
Operating conditions .............................0 to +35°C, 20 – 80% RH non-condensing
Storage conditions ................................-25 to +60°C 10 - 90% RH non-condensing
Dimensions (L x W x H) ........................113 x 48 x 28 mm
Weight approx. ..................................... 63 g (charging device), 75 g (plug in power supply)

The charger requires the plug in power supply attached, a high power USB socket or a standard 

USB socket (with charge current limitation) for operation.
Different battery sizes can be used in both charging slots with the help of slider contacts (1). 

Only the same battery types (AA, AAA, Ni-Cd, Ni-MH, Li-Ion) may be used for each charging 

process. The capacity can vary.
•   Connect the USB cable enclosed with the output at the plug in power supply and with the 

small micro USB plug with the socket “INPUT 5V” at the charger. 

•   Plug the plug-in power supply into the freely accessible power socket. The operational dis-

play on the plug-in power supply lights up.

•   The charger carries out a short functions test. The status displays (2) briefly light up red and 

green and go out after a short time. The operational test is concluded. 

•   Insert the batteries into the charging slot at the right polarity. Pull the slider contact backwards 

and let it slide to the contact on the battery. Please note the polarity details in the charging slot 

and for good contact.

•   The battery is tested and the charging process starts automatically after a short time. The 

status display lights up red during the charging operation.

•  Repeat this with a second battery.
•   The charger switches off automatically or starts the trickle charging for each individual cell 

with Ni-Cd and Ni-MH batteries. The end of the charging process is signaled with a green 

display.

•  Take the batteries out of the charging slot and unplug the charger.
Display overview (for each charging slot)

Stand-By, no battery inserted, 
Batteries inserted with incorrect polarity

Display off

Charging process

Display lights up red

Charging process ends

Display lights up green

Fault (defective batteries, primary batteries etc) Display flashes red

The charger is equipped with an automatic charging shutdown, which automatically ends the 

charging process on reaching the parameters typical to the batteries or independently switches 

to conservation load mode with Ni-Cd and Ni-MH batteries. The battery is kept at full power in 

this mode without being overcharged or damaged.

 

 A slight heating of the batteries during the charging is normal. Never cover 

Li-Ion

Charge end voltage

4.2 V (±2%)

Li-Ion

Charge end current

<150 mA

Li-Ion

Charging process

CC - CV (Constant current, 

constant voltage)

Li-Ion / Ni-Cd / Ni-MH

Safety timer

8 h

Ni-Cd / Ni-MH

Minus-Delta-U (-dV)

Ni-Cd / Ni-MH

Nil-Delta-U (0dV)

Ni-Cd / Ni-MH

Trickle charging

100 mA (pulsing)

The intelligent charging technology automatically recognizes bad or defective batteries and 

shows this in the status display (2). 
If the status display of the corresponding charging slot flashes red, these cells have a defect 

and cannot be charged. Replace defective cells.

The charging time up to reaching the charge end voltage depends on several parameters e.g. 
•  the capacity (mAh, the larger, the longer the charging time)
•  the charging status of the batteries (full, partially charged or empty)
•  the ambient temperature (this should possibly amount to 20 - 25°C)
•  the general status (old) of batteries.
The charging time can be roughly determined by a simple calculation formula.
Charging time in h = 

Battery capacity in mAh x 1.

 

Charging current in mA.