CN2508409Y - Lead-acid battery - Google Patents

Abstract

The utility model relates to a lead acid battery pack for making all the float charge voltage of all batteries balanced. The utility model comprises a plurality of storage batteries which are mutually connected in series, a voltage egualizer (3) bridges positive and negative collecting bars of each storage battery, the voltage egualizer (3) comprises a casing body, and a divided circuit for dividing the charging current of the battery is arranged in the casing body, the divided circuit is provided with an upper threshold value voltage detecting circuit and a primary control circuit connected with the upper threshold value voltage detecting circuit, the output terminal of the primary control circuit is connected with equalization and current-limited circuits, and the divided circuit is also provided with an upper threshold value voltage detecting circuit and a secondary control circuit connected with the upper threshold value voltage detecting circuit. The utility model is suitable for the float charged backup power source utilization occasions.

Description

Lead-acid battery pack

Technical field

The utility model relates to a storage battery pack for battery voltage balance.

Background technique

Fixed valve-regulated sealed lead-acid batteries are generally operated under the state of floating charge, usually float-charged by the rectifier, so that each battery in the battery pack is in a sufficient state for use in case of power failure. However, due to the inconsistency of the storage battery in the production and assembly process, the differences of each battery are caused, so that the floating charge voltage of each battery deviates. And with the increase of the floating charging process, the deviation of the floating charging voltage will further increase. Because in the series circuit, the current passing through each battery is the same, but because the energy storage efficiency of each battery is different, the battery with high efficiency stores energy faster, so the voltage rises faster, while the battery with low efficiency stores energy faster. Slow, so the voltage rises slowly, so the float voltage of each battery deviates during the float charge process. If the float charge voltage of a certain battery is too low, the battery may be insufficiently charged and fail, which will cause danger to the operation of the equipment attached to the battery pack, such as communication; if the float charge voltage of a certain battery is too high, it will accelerate the corrosion of the battery , severe dehydration, leading to premature end of service life. Therefore, countries have put forward strict requirements on the uniformity of floating charge voltage of VRLA battery packs. Both the British Standard (BS) and the German Industrial Standard (DIN) stipulate the limit of the uniformity of the floating charge voltage of the fixed lead-acid battery. If the float charge voltage of a certain battery exceeds the specified limit, it is allowed to carry out an equal charge according to the standard. , if the normal voltage cannot be restored after equalizing charging, the battery will be judged as a waste product. China's communications industry has stricter requirements on the uniformity of the floating charge voltage than the above-mentioned standards. However, the uniformity of float charge is still a difficult problem at home and abroad. The float charge voltage deviation of batteries from many manufacturers exceeds 200mV, which has become the main reason affecting battery performance.

Contents of invention

The technical problem to be solved by the utility model is to equalize the floating charge voltage of each battery in the lead-acid battery pack, and provide a lead-acid battery pack so that the charging current of the battery with high energy storage efficiency can be reduced.

The technical scheme adopted by the lead-acid storage battery pack of the utility model is to have several storage batteries connected in series. The body is provided with a shunt circuit that can shunt the charging current of the battery.

The shunt circuit can be provided with a lower threshold voltage detection circuit and its connected primary control circuit, the output end of the primary control circuit is connected with an equalization and current limiting circuit, and the shunt circuit is also provided with an upper threshold voltage The detection circuit and its connected secondary control circuit, the output terminal of the secondary control circuit is connected with the lower threshold voltage detection circuit.

The shunt circuit can also be a voltage stabilizer.

The floating charging current of each battery in the storage battery pack is the same, when the voltage of one or some batteries gradually becomes higher during the floating charging process, the shunt circuit of the voltage equalizer in the utility model can shunt the floating charging current to reduce Charging current; the higher the battery voltage, the larger the shunt current, and the smaller the charging current. On the contrary, the shunt current is small, so that the floating charge voltage of each battery is balanced.

The utility model can set a lower voltage threshold. When the battery voltage is lower than a certain set threshold, the shunt current is reduced to approximately zero. The self-discharge of the battery and the capacity loss caused by the shunt effect of the equalizer during the discharge process. In addition, it can also be designed that when the battery voltage is higher than a certain threshold, the shunt current of the equalizer is also reduced to approximately zero. This performance ensures the normal progress of the battery activation and charging process and also protects the equalizer itself. This is because The voltage of the battery is very high during the activation and charging process. If the equalizer does not have a high-voltage protection function, the shunt current through the voltage equalizer will be very large, which may not only cause the battery to be insufficiently charged, but also easily cause the equalizer device to heat up, and even cause burn out. The utility model provided with the lower threshold voltage detection circuit and its control circuit, the upper threshold voltage detection circuit and its control circuit has this function.

The voltage equalizer in the utility model can be built in the battery, that is, the voltage equalizer is built in the battery by connecting the voltage equalizer on the positive and negative lead-out bus bars of the battery.

In the utility model, since each battery in the storage battery pack is connected with a voltage equalizer, and the voltage equalizer is provided with a shunt circuit for shunting the charging current, the energy storage efficiency is high. The battery with a high voltage during charging has a large shunt current, and vice versa. The current is small, so that the voltage of each battery can be balanced.

Description of drawings

Fig. 1 is a schematic diagram of the structure of a single battery in the utility model;

Fig. 2 is the structural representation of battery pack of the present utility model;

Fig. 3 is a kind of shunt circuit schematic diagram of the voltage equalizer in the utility model;

Fig. 4 is the V～I curve diagram of Fig. 3 circuit battery voltage V and shunt current I;

Fig. 5 is another kind of shunt circuit schematic diagram of the voltage equalizer in the utility model;

Fig. 6 is a V-I curve diagram of the battery voltage V and the shunt current I in the circuit of Fig. 5 .

Detailed ways

Implementation mode 1:

The lead-acid battery pack has N batteries connected in series as shown in Figure 2, and as shown in Figure 1, the positive bus bar 1 connected to the positive pole 2 and the negative bus bar 5 connected to the negative pole 4 of each battery are shown in Figure 1 There is a voltage equalizer 3 connected across the top, and the voltage equalizer 3 has a housing which is provided with a shunt circuit that can shunt the charging current of the battery. As shown in Figure 3, the shunt circuit is provided with a lower threshold voltage detection circuit 8 and its Connected primary control circuit 9, the output terminal of primary control circuit 9 is connected with equalization and current limiting circuit 10, this shunt circuit is also provided with upper threshold voltage detection circuit 6 and its connected secondary control circuit 7, secondary The output terminal of the control circuit 7 is connected with the lower threshold voltage detection circuit 8 . Among them, the lower threshold voltage detection circuit 8 is composed of resistors R3 and R4 connected in series, the primary control circuit 9 is composed of a voltage regulator Z2 connected to a resistor R5, and the equalization and current limiting circuit 10 is composed of a triode T and a resistor R6 connected to its collector. , the upper threshold voltage detection circuit 6 is composed of resistors R1 and R2 in series, and the secondary control circuit 7 is composed of a voltage regulator Z1; the input terminal of Z2 is connected to the connection point of R3 and R4, the T base is connected to the connection point of Z2 and R5, and Z1 The input end is connected to the connection point of R1 and R2, and the output end of Z1 is connected to the connection point of R3 and R4.

When the battery voltage is low, the voltages of the detection voltage points L and H of the lower threshold voltage detection circuit 8 and the upper threshold voltage detection circuit 6 are not enough to trigger the voltage regulator Z2 of the control circuit 9 and the voltage regulator Z1 of the control circuit 7 is turned on, so the triode T in the equalization and current limiting circuit 10 is cut off, and the voltage equalizer 3 does not function as a shunt. When the battery voltage exceeds the lower threshold, the lower threshold voltage detection circuit 8 detects that the voltage at the voltage point L reaches the trigger voltage of the voltage regulator Z2 in the control circuit 9, and Z2 is turned on, so that the triode T is turned on, and the charging current of the battery is shunted . The voltage of the battery increases gradually, the shunted current increases gradually, and the resistor R6 acts as a current limiter. When the voltage of the battery is high enough to exceed the upper threshold, such as when charging with a large current, the detection voltage point H voltage of the upper threshold voltage detection circuit 6 reaches the trigger voltage of the voltage regulator Z1 in the control circuit 7, and Z1 is turned on to make point L The voltage drops, so that Z2 is restored to cut off, the transistor T is cut off, and the voltage equalizer 3 does not function as a shunt.

Implementation mode 2:

In this lead-acid battery pack, the shunt circuit in the voltage equalizer 3 uses a voltage stabilizing device composed of electronic components to realize the shunt. It is installed after the battery activation and charging is completed, and in occasions where the requirements for self-discharge are not high.

Claims (4)

1, lead-acid batteries, have some the storage batterys of series connection mutually, it is characterized in that in the positive and negative exit cross-over connection of every described storage battery one voltage equalizer (3) being arranged, voltage equalizer (3) has that a housing is provided with in it can be to the shunt circuit of battery charge shunting.

2, lead-acid batteries as claimed in claim 1, it is characterized in that the one-level control circuit (9) that described shunt circuit is provided with threshold voltages testing circuit (8) and is connected, the output of one-level control circuit (9) is connected with balanced and current-limiting circuit (10), the secondary control circuit (7) that described shunt circuit also is provided with upper threshold voltage testing circuit (6) and is connected, the output of secondary control circuit (7) is connected with threshold voltages testing circuit (8).

3, lead-acid batteries as claimed in claim 2, it is characterized in that threshold voltages testing circuit (8) is made of resistance R 3, R4 series connection, one-level control circuit (9) is connected and composed by pressurizer Z2 and resistance R 5, balanced and current-limiting circuit (10) is made of triode T and resistance R that collector electrode connects 6 thereof, upper threshold voltage testing circuit (6) is made of resistance R 1, R2 series connection, and secondary control circuit (7) is made of pressurizer Z1; The Z2 input links to each other with R3, R4 tie point, and the T base stage links to each other with Z2, R5 tie point, and the Z1 input links to each other with R1, R2 tie point, and the Z1 output links to each other with R3, R4 tie point.

4, lead-acid batteries as claimed in claim 1 is characterized in that described shunt circuit is a pressurizer.

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