Battery Auto Charger Specification Design

An advanced four (seven) stage charging program is written inside the automatic charger. While the battery is fully charged, the service life of the battery can be effectively extended.

Soft start
At the moment when the charger is energized, the power is buffered from small to large, which has a buffering protection effect on the charger when it is started.

Constant current
At this stage, the charger outputs the rated current for fast charging to increase the charging rate. The voltage of the battery gradually increases. At the same time, in order to prevent the battery from being overcharged, the charging voltage of the charger is limited to a safe value range. When the charging voltage rises to the set value, the charging current will begin to decrease slowly. At this time, the charger enters the constant voltage charging stage and continues to replenish the battery.

Constant voltage
At this stage, the charging current of the charger will gradually decrease, which can reduce the heating and vaporization of the battery and effectively avoid premature damage to the battery due to excessive aging. When the battery capacity reaches approximately 90%, the indicator light will briefly turn orange and the charger will enter the top-off phase.

Float charge
At this stage, the charger only outputs a lower voltage and smaller current to charge the battery. In this way, 100% capacity of the battery can be guaranteed at any time, and the battery will not bear unnecessary burdens, so as to prolong the service life of the battery as much as possible. At this time, the indicator light is green, which means that the battery capacity is basically fully charged.

Basic Information

Input Voltage : 100 ~ 240Vac, Min. 90Vac, Max 265Vac

Target Battery Voltage : 12V Lead Acid Battery

Output Current: Max. 6A

Output Power: 72W

Operation temperature : -40°C, +85°C

Automatic function: Auto Start/Stop

Meter: Voltage, Amp Current

Output Protect: Output reverse connection protection

Input

Frequency: 47~63Hz

Efficiency: >85%

Leakage Rate: <3.5mA/240Vac

Surge Current: 12A/230Vac

AC Current: 0.36A/230Vac

Output

Open Circuit Voltage: 13.8Vdc

Max. Output Power: 72W

Max. Output Current: 6A

Recommend Battery capacity: 18~90Ah

Open Circuit power waste: <1.3W

Voltage ripple: ≤50mV

Voltage precision: ≤1%

Battery Leakage current: <30mA

Battery Class: Lead Acid Battery

Protect

Output overload protect: The charger will stop its output when the voltage exceeds or reaches ≥14Vdc, with the Red LED indicator turning ON. It will resume operation when the output voltage falls below 14Vdc.

Over current / Short circuit: Limited current

Temperature protect: When the ambient temperature exceeds 30°C, the charger’s rated output power will gradually decrease as the temperature rises. Once it exceeds 60°C, the charger will stop outputting power. When the temperature drops below the cutoff point, the charger will automatically restore normal output.

Cooling method: Nature cool

Function

Start mode: Soft start

Constant current: When the main battery voltage drops below ≤ 12.5Vdc, the charging output pressure is activated for fast charging to increase the charging rate. At this time, the indicator light(L) will illuminate in red

Constant voltage: When the charger’s output voltage reaches 13.9Vdc and remains relatively stable, the charging current gradually decreases. This helps reduce battery heating and vaporization, effectively preventing excessive aging and premature damage to the battery. At this time, the indicator light(L) will illuminate in red

Float charging: When the battery capacity reaches 90%, the charger enters the float charging stage to continue replenishing the battery. At this time, the indicator light (L) will in green.

Environment

Operation temperature: -20°C ~ +50°C

Storage temperature: -40°C ~ +85°C

Operating humidity: 20~90%Rh

Storage humidity: 0~95%Rh

Vibration resistance: 10~500Hz 2G 10 minutes/cycle, x/y/z axis 60 minutes

Auto start/stop control

Auto stop charge: When the changing voltage exceeds ≥13.8Vdc, the charging current will continue to gradually decrease. When the charging current drops below 0.6A, the charger will automatically stop outputting power.

Pulse charging: It is a timely replenishment control method for the natural consumption of the battery, which not only keeps the battery in the best working condition at all times. It can also minimize the vaporization of the battery and the sulfide corrosion reaction of the plates,
avoid early damage and aging of the battery, and effectively extend the service life of the battery. At this time, the indicator light (R) lights green intermittently.

Auto activate charging: When the battery voltage is ≤13.2Vdc , the charger will automatically activate and return to the corresponding charging state.

Alarm

Relay alarm: When the battery voltage is ≤12.5Vdc or when the charger fails to output, the relay contact is closed.

Indicator light alarm: When the output voltage of the charger is ≥14Vdc, the charger stops outputting, and the indicator light (R) is red at this time.

Reverse protection

When the charger’s output terminal is connected reversely, the charger stops output; when the reverse connection is removed, the charger will automatically resume output (when the battery voltage is higher than 5Vdc): If the battery voltage is lower than 5Vdc at this time, you need to protect it first.
When the power supply of the input terminal is confirmed to be normal, disconnect the output terminal and then connect the output terminal, the charger will automatically restore the output.

Nomad XR4000 battery balancing circuit

原文:http://users.cecs.anu.edu.au/~luke/xr4000batbal.html

Nomad XR4000 battery balancing circuit

The nomad XR 4000 robot has four lead acid batteries in series. The problem is that even with batteries from an identical batch, minute differences between the batteries makes them charge unevenly.

To combat this problem we made the following battery balancing circuit.

The problem is that batteries that are charged has a potential of over 13.8 volts, while other batteries have potentials of only 10 volts and don’t get charged. One circuit is placed in parallel with each of the batteries.

If the potential across the battery is lower than 13.8 volts, the circuit does nothing, if the potential raises above 13.8 the transistor starts to switch on placing the resistor in parallel with the battery until the potential is pulled down to 13.8. You can think of it as a glorified zener diode, with a lot sharper on elbow on the voltage vs current curve, the LM431 is a tunable zener diode. A potentiometer allows you to set the ~13.8 volt on/off point for the circuit. We set the pot. using a variable workshop supply to just start to turn on at 13.8 volts (you’ll see the current drawn go way up when it does).

Nomad XR4000 電池均衡電路

Nomad XR 4000 機器人採用了四個串聯的鉛酸電池。問題是,即使是來自相同批次的電池,微小的差異也會導致它們充電不均勻。

為了解決這個問題,我們設計了以下的電池均衡電路。

問題在於已經充電的電池電位超過了13.8伏特,而其他電池的電位只有10伏特,無法充電。我們將一個電路放置在每個電池的並聯位置。

如果電池上的電位低於13.8伏特,該電路將不起作用;如果電位升至13.8伏特以上,晶體管開始開啟,將電阻與電池並聯,直到電位降至13.8伏特。您可以將其視為一種高級齊納二極管,具有更陡的電壓與電流曲線彎曲點,LM431是可調的齊納二極管。一個電位計允許您設定電路的約13.8伏特的開/關點。我們使用可變的工作室電源設置電位計,以在13.8伏特時開始啟動(當它啟動時,您將看到電流大幅上升)。

Because of the potential worst case scenarios for the system the resistor and transistor have to be rated quite highly. In reality though the resistor and transistor rarely get warm.

由於系統的潛在最壞情況,電阻器和晶體管必須有相當高的額定值。然而實際上,電阻器和晶體管很少會變熱。

The circuit has been in the robot for over two years and the batteries have not had to be replaced or charged on separate chargers since.

這個電路已經在機器人中使用了兩年多,而且自那時以來電池不需要更換,也不需要單獨充電器充電。”