CN203251112U - Equalization charging management device used for lithium ion battery assembly of spacecraft - Google Patents

Abstract

The utility model discloses an equalization charging management device used for a lithium ion battery assembly of a spacecraft. The equalization charging management device includes N equalization modules; one equalization module is arranged at two ends of one single battery in a battery assembly formed through the series connection of N single battery; each equalization module includes an MOS tube switch, a comparator, a resistor R0, a resistor R1, a resistor R2, a resistor R3 and a resistor R4; and the equalization charging management device compares the voltage average value of the whole battery assembly with the voltage of the single batteries, when the voltage average value is higher, the equalization charging management device continues to charge the single batteries in an original mode, and when the voltage of the single batteries is higher, and switches are switched off, the bypass resistors of the single batteries shunt charging current, such that the whole battery assembly can be equalized. The equalization charging management device is advantageous in simplicity and better equalization effect.

Description

A kind of equalizing charge manager of the lithium ion battery group for spacecraft

Technical field

The utility model relates to the power management techniques field, is specifically related to a kind of equalizing charge manager of the lithium ion battery group for spacecraft.

Background technology

The lithium ion battery group is little with its volume, lightweight, specific energy is high, long and the advantage such as quick of charging of life-span is applied in the space flight energy-storage travelling wave tube, needing in the spacecraft that multisection lithium battery is combined into battery pack uses, but because inside battery property difference, working temperature and the difference that recycles number of times, the battery behavior that cell shows have distinguish, concrete is presented as that state-of-charge is uneven, the enclosed pasture efficient of lithium ion battery is very high, more than 90%, if because the internal diversity of battery itself or the difference of external environment condition slightly descend other batteries of Performance Ratio of certain cell, so through after the charge and discharge cycles repeatedly, the state-of-charge of this battery just and the serious imbalance of other batteries, the imbalance between the battery cell will worsen in time.On the other hand, lithium battery does not have overcharge resistance performance, and its voltage can constantly rise along with charging, and overvoltage will produce nonvolatil damage to battery.The as above characteristic of lithium battery has been brought huge challenge to the Charge Management of battery pack, unbalanced phenomena meeting between battery cell so that battery capacity diminish, even may cause the serious security hidden troubles such as the overdischarge of overcharging, in order to reduce this harm, in the charging process of battery pack, to use equalizing circuit that charging process is managed.

The fast charge method that common lithium cell charging equipment often adopts constant current and constant voltage to combine, at first with constant current charge to the predeterminated voltage value, then use constant voltage charge to finish remaining charging.This method can be reduced to minimum with gas output.This mode has better guaranteed the safety of battery by the combination of front two kinds of charging modes.Although charging control circuit is comparatively complicated, because of its charging interval short, charge efficiency is high, so occupy an leading position in the charging of lithium ion battery.In the charging process battery pack is carried out the equalizing charge management, the equalizing charge of battery pack becomes a difficult problem maximum in the batteries charging, also is a large focus of current batteries charging research, and balanced way commonly used has following several now:

Battery optimization, battery screening, battery use: can only guarantee under the state that battery pack is brought into use with upper type, the balance in the process of work between each battery cell, but can not guarantee safety and the coupling of the whole use procedure of battery pack; These balanced ways of being finished by battery itself coupling can not be basic the solution equalization problem.

Negative approach to the question of equilibrium: passive charging balance is to finish the charging balance of each battery by discharge, in charging process, determine the highest monomer of charging voltage, its electric weight is discharged by bypass resistance, so that the slower battery of this battery and other charging coordinates, thereby reach the effect of balance.Loss to energy is too high, generally will not adopt.

Energy transfer is balanced: the energy transfer equalizing charge can be so that the energy in the battery produces mobile between unbalanced battery cell, by external control the energy in the high energy battery is delivered in the low-energy battery and to be gone, mainly be to finish by energy-storage travelling wave tube, energy-storage travelling wave tube is divided into two kinds of inductance and electric capacity, be divided into two kinds so this mode is also corresponding, but the control circuit of this mode is too complicated, and the energy-storage travelling wave tube of equalizing circuit itself and the loss of switch are so that their advantage in the application of great current cell group is more obvious.In the charging of the small-capacity cells that 100Ah is following, the cost performance of these modes is not high, and gives the design of circuit itself, and cost etc. have all been brought larger difficulty, and inapplicable.

The utility model content

In view of this, the utility model provides a kind of equalizing charge manager of the lithium ion battery group for spacecraft, can carry out equalizing charge to the lithium ion battery group, simultaneously, this manager simple in structure, old is cheap.

The equalizing charge manager of a kind of lithium ion battery group for spacecraft of the present utility model, the equalizing charge manager comprises N balance module, a balance module is arranged on the two ends of a cell in the battery pack that is composed in series by N cell, this balance module comprises metal-oxide-semiconductor type switch, comparator, resistance R 0, R1, R2, R3 and R4, wherein:

One end of resistance R 1 connects the high potential Vcell+ end of cell, is connected with the electronegative potential LO end of battery pack behind the other end series resistance R2 of resistance R 1;

One end of resistance R 4 connects the electronegative potential Vcell-end of cell, is connected with the high potential HI end of battery pack behind the other end series resistance R3 of resistance R 4;

Draw line between resistance R 1 and the resistance R 2 and be connected with the positive input terminal of comparator, draw line between resistance R 4 and the resistance R 3 and be connected with the negative input end of comparator; The output of comparator is connected with 1 pin of metal-oxide-semiconductor switch;

2 pin ground connection of metal-oxide-semiconductor switch, the high potential Vcell+ end of 3 pin order body batteries is connected with the electronegative potential Vcell-end of cell behind the 4 pin series resistance R0; The stiff end of the switch shrapnel of metal-oxide-semiconductor type switch is connected to 4 pin of metal-oxide-semiconductor switch, and when comparator was not exported, the free end of switch shrapnel was unsettled, and when comparator had output, the free end of switch shrapnel was connected to 3 pin, and then 3 pin and 4 pin are communicated with;

Described resistance R 1, R2, R3 and R4 satisfy following relation:

When the cell number was 7, the resistance of described resistance R 0, R1, R2, R3 and R4 was respectively: 1 megohm, 1 megohm, 7 megohms, 7 megohms and 1 megohm.

The utlity model has following beneficial effect: equalizing charge manager of the present utility model is by the average voltage of more whole Battery pack and the voltage of cell, when the average voltage of whole Battery pack is higher, keeps original mode and continue this cell is continued charging; Switch closure when monomer battery voltage is higher uses the resistance of cell bypass that charging current is shunted, thereby makes whole Battery pack reach balanced, and this balanced way structure is relatively simple, and preferably portfolio effect is arranged.

Description of drawings

Fig. 1 is that available technology adopting constant voltage and current constant mode are to the schematic diagram of battery charging.

Fig. 2 is the schematic diagram of equalizing charge manager of the present utility model.

Fig. 3 is the schematic diagram of a balance module of the present utility model.

Embodiment

Below in conjunction with the accompanying drawing embodiment that develops simultaneously, the utility model is described in detail.

The utility model provides a kind of equalizing charge manager of the lithium ion battery group for spacecraft, shown in Fig. 2 and 3, this equalizing charge manager comprises N balance module, a balance module is arranged on the two ends of a cell in the battery pack that is composed in series by N cell, this balance module comprises metal-oxide-semiconductor type switch, comparator, resistance R 0, R1, R2, R3 and R4, wherein:

One end of resistance R 1 connects the high potential Vcell+ end of cell, is connected with the electronegative potential LO end of battery pack behind the other end series resistance R2 of resistance R 1;

One end of resistance R 4 connects the electronegative potential Vcell-end of cell, is connected with the high potential HI end of battery pack behind the other end series resistance R3 of resistance R 4;

Draw line between resistance R 1 and the resistance R 2 and be connected with the positive input terminal of comparator, draw line between resistance R 4 and the resistance R 3 and be connected with the negative input end of comparator; The output of comparator is connected with 1 pin of metal-oxide-semiconductor switch;

2 pin ground connection of metal-oxide-semiconductor switch, the high potential Vcell+ end of 3 pin order body batteries is connected with the electronegative potential Vcell-end of cell behind the 4 pin series resistance R0; The stiff end of switch shrapnel is connected to 4 pin of metal-oxide-semiconductor switch, and when comparator was not exported, the free end of switch shrapnel was unsettled, and when comparator had output, the free end of switch shrapnel was connected to 3 pin, and then 3 pin and 4 pin are communicated with;

Resistance R 1, R2, R3 and R4 satisfy following relation:

The lithium battery group of the present embodiment is composed in series by 7 batteries, each single battery balance module in parallel carries out the equalizing charge management, the composition of whole equalizing circuit and battery as shown in Figure 2, battery end is the non-zero negative terminal voltage that the sampling resistor of the constant current charge of battery brings.

In the charging of battery pack, it is the relation of series connection between the battery cell, the voltage of battery cell is relevant with the up and down battery of series connection, its negative pole point position is by the voltage of following a string battery cell and decision, and a string battery of the voltage difference of itself and lower end determined the negative pole current potential of a higher batteries with voltage.In charging process, the battery of each battery cell is constantly changing, so the both positive and negative polarity current potential of each battery cell is to float to change.

As shown in Figure 3, each single battery shunt resistance R0 in parallel, and controlled the output of this road electric current by switch; Each module collection and calculate the anodal negative pole of whole battery pack and the positive and negative terminal voltage of each battery between relation, obtain the comparison of average voltage and the single battery voltage of whole Battery pack, compare gained voltage, higher such as single battery voltage, then open the switch of battery pack parallel connection by the comparator output HIGH voltage, by the resistance charging current of releasing, thereby stop the charging to battery cell, thereby in total charging process, the battery that charging is fast or voltage is slightly high uses slow as far as possible speed, so that the charging effect that the acquisition of whole Battery pack is complementary.

For comparator, for obtain the comparison between single battery and the whole Battery pack by comparatively simple circuit, carry out the as above calculating of figure comparator, wherein LO and HI represent respectively anode and the negative terminal voltage of whole Battery pack, use V _BAT+And V _BAT-Represent.

$\frac{V_{\mathrm{cell}+}-V_{\mathrm{comp}+}}{{\mathrm{<figure-callout\; id="1"\; label="R"\; filenames="HDA00003048653600011.png,HDA00003048653600021.png"\; state="\{\{state\}\}">R</figure-callout>}}_1}=\frac{V_{\mathrm{comp}+}-V_{\mathrm{BAT}-}}{R_2}$

Arrangement obtains

$V_{\mathrm{comp}+}=\frac{R_2*V_{\mathrm{cell}+}+{\mathrm{<figure-callout\; id="1"\; label="R"\; filenames="HDA00003048653600011.png,HDA00003048653600021.png"\; state="\{\{state\}\}">R</figure-callout>}}_1*V_{\mathrm{BAT}-}}{{\mathrm{<figure-callout\; id="1"\; label="R"\; filenames="HDA00003048653600011.png,HDA00003048653600021.png"\; state="\{\{state\}\}">R</figure-callout>}}_1+R_2}$

In like manner, can obtain V _Comp-Formula be:

$V_{\mathrm{comp}-}=\frac{{\mathrm{<figure-callout\; id="3"\; label="R"\; filenames="HDA00003048653600021.png"\; state="\{\{state\}\}">R</figure-callout>}}_3*V_{\mathrm{cell}-}+{\mathrm{<figure-callout\; id="4"\; label="R"\; filenames="HDA00003048653600021.png"\; state="\{\{state\}\}">R</figure-callout>}}_4*V_{\mathrm{BAT}+}}{{\mathrm{<figure-callout\; id="3"\; label="R"\; filenames="HDA00003048653600021.png"\; state="\{\{state\}\}">R</figure-callout>}}_3+{\mathrm{<figure-callout\; id="4"\; label="R"\; filenames="HDA00003048653600021.png"\; state="\{\{state\}\}">R</figure-callout>}}_4}$

The positive and negative of comparator compared, can obtain

$V_{\mathrm{comp}+}-V_{\mathrm{comp}-}=\frac{R_2*V_{\mathrm{cell}+}+{\mathrm{<figure-callout\; id="1"\; label="R"\; filenames="HDA00003048653600011.png,HDA00003048653600021.png"\; state="\{\{state\}\}">R</figure-callout>}}_1*V_{\mathrm{BAT}-}}{{\mathrm{<figure-callout\; id="1"\; label="R"\; filenames="HDA00003048653600011.png,HDA00003048653600021.png"\; state="\{\{state\}\}">R</figure-callout>}}_1+R_2}-\frac{{\mathrm{<figure-callout\; id="3"\; label="R"\; filenames="HDA00003048653600021.png"\; state="\{\{state\}\}">R</figure-callout>}}_3*V_{\mathrm{cell}-}+{\mathrm{<figure-callout\; id="4"\; label="R"\; filenames="HDA00003048653600021.png"\; state="\{\{state\}\}">R</figure-callout>}}_4*V_{\mathrm{BAT}+}}{{\mathrm{<figure-callout\; id="3"\; label="R"\; filenames="HDA00003048653600021.png"\; state="\{\{state\}\}">R</figure-callout>}}_3+{\mathrm{<figure-callout\; id="4"\; label="R"\; filenames="HDA00003048653600021.png"\; state="\{\{state\}\}">R</figure-callout>}}_4}$

$=(\frac{R_2}{{\mathrm{<figure-callout\; id="1"\; label="R"\; filenames="HDA00003048653600011.png,HDA00003048653600021.png"\; state="\{\{state\}\}">R</figure-callout>}}_1+R_2}{V}_{\mathrm{cell}+}-\frac{R_3}{{\mathrm{<figure-callout\; id="3"\; label="R"\; filenames="HDA00003048653600021.png"\; state="\{\{state\}\}">R</figure-callout>}}_3+R_4}{V}_{\mathrm{cell}-})-(\frac{R_4}{{\mathrm{<figure-callout\; id="3"\; label="R"\; filenames="HDA00003048653600021.png"\; state="\{\{state\}\}">R</figure-callout>}}_3+R_4}{V}_{\mathrm{BAT}+}-\frac{R_1}{{\mathrm{<figure-callout\; id="1"\; label="R"\; filenames="HDA00003048653600011.png,HDA00003048653600021.png"\; state="\{\{state\}\}">R</figure-callout>}}_1+R_2}{V}_{\mathrm{BAT}-})$

If select $\frac{R_2}{{\mathrm{<figure-callout\; id="1"\; label="R"\; filenames="HDA00003048653600011.png,HDA00003048653600021.png"\; state="\{\{state\}\}">R</figure-callout>}}_1}=\frac{R_3}{R_3}=m$

Then can be with above-mentioned formula arrangement:

$V_{\mathrm{comp}+}-V_{\mathrm{comp}-}=\frac{m}{m+1}[(V_{\mathrm{cell}+}-V_{\mathrm{cell}-})-\frac{1}{m}(V_{\mathrm{BAT}+}-V_{\mathrm{BAT}-})]$

The positive and negative both end voltage of comparator is the monomer battery voltage of m/ (1+m) and the ratio of whole Battery pack dividing potential drop, if when getting m and being whole Battery pack joint number 7, this module just can arrive the function of comparison single battery voltage and whole Battery pack dividing potential drop, and this moment, the multiplication factor of two parts voltage was 7/8=0.875.

In sum, above is preferred embodiment of the present utility model only, is not be used to limiting protection range of the present utility model.All within spirit of the present utility model and principle, any modification of doing, be equal to replacement, improvement etc., all should be included within the protection range of the present utility model.

Claims (2)

1. equalizing charge manager that is used for the lithium ion battery group of spacecraft, it is characterized in that, the equalizing charge manager comprises N balance module, a balance module is arranged on the two ends of a cell in the battery pack that is composed in series by N cell, this balance module comprises metal-oxide-semiconductor type switch, comparator, resistance R 0, R1, R2, R3 and R4, wherein:

One end of resistance R 1 connects the high potential Vcell+ end of cell, is connected with the electronegative potential LO end of battery pack behind the other end series resistance R2 of resistance R 1;

One end of resistance R 4 connects the electronegative potential Vcell-end of cell, is connected with the high potential HI end of battery pack behind the other end series resistance R3 of resistance R 4;

Draw line between resistance R 1 and the resistance R 2 and be connected with the positive input terminal of comparator, draw line between resistance R 4 and the resistance R 3 and be connected with the negative input end of comparator; The output of comparator is connected with 1 pin of metal-oxide-semiconductor switch;

2 pin ground connection of metal-oxide-semiconductor switch, the high potential Vcell+ end of 3 pin order body batteries is connected with the electronegative potential Vcell-end of cell behind the 4 pin series resistance R0; The stiff end of the switch shrapnel of metal-oxide-semiconductor type switch is connected to 4 pin of metal-oxide-semiconductor switch, and when comparator was not exported, the free end of switch shrapnel was unsettled, and when comparator had output, the free end of switch shrapnel was connected to 3 pin, and then 3 pin and 4 pin are communicated with;

Described resistance R 1, R2, R3 and R4 satisfy following relation:

2. the equalizing charge manager of a kind of lithium ion battery group for spacecraft as claimed in claim 1, it is characterized in that, when the cell number was 7, the resistance of described resistance R 0, R1, R2, R3 and R4 was respectively: 1 megohm, 1 megohm, 7 megohms, 7 megohms and 1 megohm.

Images