L4 is an excellent choice if you need a universal charger for working with batteries of different types and sizes. The very easy-to-read display, which is tilted towards the front, always provides information about all the important key figures relating to the operating process when charging or discharging the batteries.

Keeppower L4 Intelligent fast charger with analysis function.

KEEPPOWER L4 is an intelligent charger for NiMH batteries and Li-ion batteries. Enables charging, discharging, testing, activating and measuring the capacity. By selecting charging currents, you can precisely adjust the charger's operation depending on the type and capacity of the rechargeable batteries.

Keeppower L4 allows charging currents up to 2A per bay through its 4A 12V power supply.

4 independently functioning charging bays allow different modes of operation for each charging bay. The backlit real-time LCD display shows the following information for each battery: Operating mode, percentage of charge, current voltage, charge / discharge current, accumulated capacity, elapsed time, internal resistance. To save energy, the backlight switches off automatically a few seconds after pressing a function key.

USB interface for connection to a computer.

Optionally, the Keeppower L4 asks for a USB interface to connect to a Windows computer. This requires installed software and a USB HID cable (both not included) can thus display more parameters and charging curves. It can save charge data and curves, export EXCEL file or redraw curves. It is easy to make comparison and analysis. (more in the instruction manual)

The following Li-Ion battery types can be charged:

10440 / 14500 / 14650 / 16340 /  17335 / 17500 / 17670 / 18350 / 18490 / 18500 / 18650 / 18700 / 20700 / 21700.
The following batteries can only be charged in slot 1 and slot 4: 25500 / 26650 / 26700
3.6V/3.7V Lithium-ion batteries.
Not suitable for protected 20700/21700 batteries. max. length 73.5 mm.

The following Ni/MH Ni/CD battery types can be charged: 

AAAA / AAA / AA / SC / C
The following batteries can only be charged in slot 1 and slot 4:  SC / C

Product information about the KEEPPOWER L4 Charger:

• Keeppower L4 charger has four intelligent charging bays that function independently.
• LCD display for real time, display operating mode, percentage of charge, current voltage, charge / discharge current, accumulated capacity, elapsed time, internal resistance. 
• 4 operating modes: charge, discharge, test and activation.
• Test the actual capacity and maximise the life of the batteries.
• Automatic detection of battery type (Li-Ion or Ni/Mh).
• USB HID interface to Windows computer.
• 12V 4A power supply included.
• 0V activation function to save deep discharged batteries.
• Max. charging current 4x 2A (2000mA)
• IC temperature monitoring to avoid overheating .
• Reverse polarity and short circuit protection.
• Automatic charge stop, charging stops automatically when battery is full.

Scope of delivery:

Keeppower L4 charger, 12V 4A power supply unit Operating instructions in English, German as download, brief instructions at "Technical data".
Operating instructions: Keeppower L4(German)

Software: KEEPPOWER_EN 1.0

USB-HDI Data Cable: USB HID Data Cable for Keeppower L4 Charger

Safety instructions:

1. only charge the batteries intended for the device.
Please always pay attention to the charging voltage setting. 3.
3. only charge batteries with the appropriate charging voltage (danger of explosion).
4. the appliance is for household use, keep away from water and moisture!
5. disassembly and modification are strictly forbidden!
6. please avoid short circuit.

*Charge parameters:

*The above parameters are laboratory tested. Approximate values may vary between charger, batteries and environment.

Quick guide:

Chargers automatically detect the Li-ion battery or Ni-MH battery.

After inserting the batteries, "Charge" flashes on the left side in the function area, the mode button can be used to select the charging (CHARGE), discharging (DISCHARGE), analysis (TEST) or activation (RESET) mode. Press "CURRENT-" or "CURRENT+" to select different currents, (charge current available: 0.5A/1 A/1.5A/2A discharge current available: 0.1 A/0.2A/0.3A/0.4A).
If you do nothing for the next 5 seconds, the charger starts working in the set mode and automatically selects the lowest charging or discharging current for the mode.

Battery information such as voltage, current, capacity, time, temperature, internal resistance is displayed on the screen during charging. Press the "SLOT" button to display the information of another channel.

Charging mode: Fully charge battery (full charge voltage:  Li-Ion 4.2V±0.05 / Ni-MH 1.45V±0.1).

Discharge mode: Discharge of the batteries to cut-off voltage with set current Li-Ion 2.8V, Ni-MH 0.9V

Test mode: Determination of the capacity by discharging the batteries, the battery is fully charged, 10 min pause, discharge (capacity measurement), 10 min pause and fully charged again.  

Reset mode: Activates NIMh batteries with high internal resistance to improve battery performance. This mode works with small currents and multiple cycles, may take longer than 10 hrs in some circumstances.

Please note: To switch to another mode or to restart the current mode, the batteries must be removed and reinserted.