Background technology
Traditional rechargeable battery is sequentially with priming mode, fast charge pattern and constant voltage mode etc. three when being chargedKind pattern is charged.When carrying out priming mode first, each battery core of rechargeable battery is charged in a manner of low current, whenWhen the voltage of each battery core reaches the first transition voltage, each battery core is filled in a manner of high current into fast charge pattern and changingElectricity, enters constant voltage mode when the voltage of one of battery core reaches the second transition voltage, then in a manner of determining voltage pairEach battery core is charged.
Traditional rechargeable battery in the fabrication process, is assembled again although battery core can be screened in advance, however, the spy of battery coreProperty, it is difficult to control to identical that particularly interior resistance, which is,.Existing charging method easilys lead to the voltage between each battery coreDifference has the phenomenon to peel off, the voltage difference between each battery core the more is become the more big.Consequently, it is possible to battery will be caused in charging,Have part battery core and first fill full, other battery cores are not filled but full, allow user can not effectively utilize all capacitances of battery.In addition, when cell charging times persistently increase, the phenomenon will become apparent from.
I No. 343141 patents in Taiwan disclose a kind of charging method of battery, refer to its accompanying drawing 5.The patent is firstConstant-current charge is carried out with the first predetermined current I1, and the voltage of each battery core for detecting battery module group in parallel.Afterwards, when itIn battery core parallel connection group when reaching the first preset voltage value V1, downgrade the electric current of above-mentioned battery core group in parallel to the second predetermined currentI2, and when the battery core parallel connection group is returned to the first preset voltage value V1, that is, judge that the electric power of battery core group in parallel almost fillsIt is full.However, above-mentioned patent does not have the electric current for illustrating how to downgrade the battery core for reaching the first preset voltage value V1 group in parallel.
In addition, also disclosing that a kind of charging method in Chinese patent CN103532191A, its accompanying drawing 1 refer to.Wherein,First battery pack and the second battery pack are in parallel relationship, and power supply 5 is all connected to via Switching Power Supply.In addition, the patentThe magnitude of voltage of the first battery pack and the second battery pack is detected using voltage check device, when both voltage differences are excessive,Recharge processor will adjust charging current, the charging current of the battery pack with low voltage is more than the electricity with high voltageThe charging current of pond group.
Above-mentioned patent is primarily directed to the battery pack being connected in parallel, not for the charging side for the battery pack being connected in seriesFormula provides any technical scheme.
The content of the invention
, can be fast the invention provides a kind of charge control method of brand-new rechargeable battery compared to prior artThe voltage difference between each battery core of series connection is reduced when being charged under mold filling formula.
In order to reach above-mentioned purpose, the invention provides a kind of charge control method of rechargeable battery, it is in fast charge patternUnder, include following steps：Step a) charges to rechargeable battery, and the inside of rechargeable battery includes multiple be connected in seriesBattery core, each battery core are respectively correspondingly connected with balancing circuitry, and the balancing circuitry can be between closed circuit state and open-circuit conditionSwitch, and the electric energy of connected battery core is consumed in the closed circuit state；Step b) measures the magnitude of voltage of each battery core；AndStep c) judges whether the difference of the maximum voltage value and minimum amount of voltage that in the magnitude of voltage of battery core is less than critical value, if judging knotFruit is yes, then for open-circuit condition and the control of each balancing circuitry is returned into step b), it is on the contrary then by with the electricity with maximum voltage valueBalancing circuitry control is closed circuit state corresponding to core, and makes other balancing circuitrys be open-circuit condition, and by the electric current of charging currentValue is adjusted to the calculated value obtained by equal to above-mentioned maximum voltage value divided by the resistance value of balancing circuitry.
Thus, in the charging process of fast charge pattern, if finding, the difference of voltage between each battery core is excessive, you can to balanceThe voltage for the battery core that circuit is controlled and makes to have maximum voltage value is maintained fixed value, and make other battery cores continue charging andMagnitude of voltage continues to increase, and then controls the difference of all battery core voltages in critical value, enables battery core balanced in charging processCompletion charging.
The charge control method of the present invention has at least following two advantages：
Advantage 1：The rechargeable battery of battery core tandem type is provided with balancing circuitry mostly, for avoiding part battery core from chargingThe problem of being overcharged in journey.The charge control method of the present invention reduces the electricity between each battery core using existing balancing circuitryPressure difference, it is not necessary to additionally increase other hardware, therefore hardware cost will not be increased.
Advantage 2：The charge control method of the present invention can make each battery core all balancedly reach deep charge, may not only prolongThe usage time of long rechargeable battery, it can more safeguard the life-span of rechargeable battery.
Brief description of the drawings
Fig. 1 is the schematic diagram of the hardware configuration of the battery charging module of present pre-ferred embodiments.
Fig. 2 a are the step flow charts of present pre-ferred embodiments.
Fig. 2 b are hookup 2a step flow charts.
Fig. 2 c are hookup 2a step flow charts.
Fig. 3 be the rechargeable battery of present pre-ferred embodiments in charging, the change of charging current and battery core current versus timeChange figure.
Fig. 4 be the rechargeable battery of control group in charging, the variation diagram of charging current and battery core current versus time.
(symbol description)
The rechargeable battery of 1 battery charging module 10
12 balancing circuitrys 121 switch
The battery core of 122 dead resistance 13 first
14 second battery core Δ V differences
The charger of 20 microcontroller 30
I priming mode II fast charge patterns
III constant voltage mode S1.1-1.18 steps
T1 the first transition voltage T2 the second transition voltages
Embodiment
Where knowing more about the feature of the present invention, the invention provides a preferred embodiment and it is described with reference to the drawingsIt is as follows, Fig. 1 is refer to Fig. 4.Same or similar part will use identical component symbol below in an example, with sideJust recognize.
So-called rechargeable battery 10 in this specification, it at least can be (but are not limited to) lithium battery, Ni-MH battery, plumbic acid electricityAny of pond.
Please include rechargeable battery with reference first to the hardware architecture diagram of Fig. 1 battery charging modules, battery charging module 110th, microcontroller 20 and charger 30.Wherein, rechargeable battery 10 includes two the first battery cores 13 being connected in series andTwo battery cores 14, the first battery core 13 and the second battery core 14 are all corresponding to be connected with balancing circuitry 12.The balancing circuitry 12 of the present embodiment wrapsContaining a switch 121 and a dead resistance 122, the positive voltage terminal of the first battery core 13 and the second battery core 14 is coupled in and itOne end of the switch 121 of corresponding balancing circuitry 12, and the other end of the both ends difference connecting valve 121 of dead resistance 122And first battery core 13 and the second battery core 14 negative voltage side, therefore, the resistance value of balancing circuitry 12 is substantially equal to dead resistance122 resistance value.It should be noted that the quantity of the battery core of rechargeable battery 10 can be two or more, the present embodiment is not limited to.
Microcontroller 20 includes universal input and output (GPIO) to perform the input of signal and output, and via for exampleAnalog-digital converter (ADC) interface and respectively with the positive voltage terminal and negative voltage side of the first battery core 13 and the second battery core 14Positive voltage terminal and negative voltage side are electrically connected with, for measuring the magnitude of voltage of the first battery core 13 and the second battery core 14.In addition, microcontrollerDevice 20 is connected via such as inter-integrated circuit (I2C) or serial peripheral interface (SPI) with charger 30, and to charger 30Control command is provided to control it.On the other hand, microcontroller 20 is connect by above-mentioned universal output input (GPIO)Mouthful and control the switch 121 of each balancing circuitry 12, by the conducting of controlling switch 121 whether, so as to control balancing circuitry 12 to existSwitched between closed circuit state and open-circuit condition.
Charger 30 is controlled by microcontroller 20 and supplies electricity to the first battery core 13 and the second battery core 14 of rechargeable battery 10,And priming mode, fast charge pattern and constant voltage mode can be carried out.
The hardware configuration of the present embodiment it is stated that finish, will be detailed below rechargeable battery charge control method it is eachIndividual step, it refer to Fig. 2 a to Fig. 3.
Please with reference first to Fig. 2 a and Fig. 3.In step S1.1, rechargeable battery 10 proceeds by charging, now, the present embodimentThe magnitude of voltage of first battery core 13 and the second battery core 14 is below the first transition voltage T1 (with reference to figure 3), makes charger 30 in preliminary fillingCharged (step S1.2) with such as 0.1 ampere of charging current under pattern I.
Step S1.3 is performed afterwards, and microcontroller 20 measures the magnitude of voltage of the first battery core 13 and the second battery core 14, and performsStep S1.4, judges whether the magnitude of voltage of the first battery core 13 and the second battery core 14 all meets or exceeds the first transition voltage T1, ifJudged result is yes, and microcontroller 20 changes control charger 30 to be charged (step S1.5) with fast charge pattern II.It is on the contrary thenStep S1.2 is returned to, maintains to be charged in a manner of priming mode I.
In fast charge pattern II, charger 30 comes the current value (such as 1 ampere) for increasing charging current to the first battery core13 and second battery core 14 charged.Enter step S1.6 afterwards, microcontroller 20 measures the first battery core 13 and the second battery core 14Magnitude of voltage, and into step S1.7 determine whether any one battery core magnitude of voltage reach the second transition voltage T2, if sentencingDisconnected result is yes, then on the contrary then enter step S1.8 into step S1.12.
In step 1.8, microcontroller 20 is by the magnitude of voltage for remeasuring the first battery core 13 of acquirement and the second battery core 14Maximum voltage value and minimum amount of voltage that, and calculate the difference DELTA V of the maximum voltage value and minimum amount of voltage that, and judge the differenceWhether value Δ V is less than critical value.If it is judged that being yes, then balancing circuitry control for open-circuit condition and is returned into stepS1.5, continue to be charged under fast charge pattern II.It is on the contrary then enter step S1.9.
In the present embodiment, above-mentioned critical value is set to the 3% of state-of-charge (State Of Charge, SOC), butNot limited to this.
Incorporated by reference to reference to figure 2b and Fig. 3.In step S1.9, present embodiment assumes that the magnitude of voltage of the first battery core 13 is more than theThe magnitude of voltage of two battery cores 14, and the difference DELTA V of maximum voltage value and minimum amount of voltage that is more than critical value, now, microcontroller 20The balancing circuitry 12 of first battery core 13 and the second battery core 14 is controlled as closed circuit state and open-circuit condition, and by charging currentCurrent value be adjusted to equal to the first battery core 13 magnitude of voltage (i.e. maximum voltage value) divided by dead resistance 122 resistance value gainedThe calculated value arrived.Now, the electric energy of the first battery core 13 will be consumed resistance 122 because of the conducting of switch 121 and be consumed, and make firstThe voltage of battery core 13 no longer rises, and the magnitude of voltage of the second battery core 14 still continues to increase, and then makes the first battery core 13 and secondThe magnitude of voltage of battery core 14 can be gradually reduced and convergence is identical.
After step S1.9, the magnitude of voltage of the first battery core 13 and the second battery core 14 is measured into step S1.10, is entered back intoJudge whether the difference DELTA V of the magnitude of voltage of the first battery core 13 and the second battery core 14 is equal to 0 in step S1.11.If difference DELTA VIn 0, then step S1.9 is returned to.It is on the contrary then return to step S1.5, revert to the maximum current value of charging current of fast charge pattern simultaneouslyContinue to charge.
Incorporated by reference to reference to figure 2c, if the magnitude of voltage of any one battery core reaches the second transition voltage T2 (subsequent stepsS1.7), no matter whether the difference DELTA V of the first battery core 13 and the second battery core 14 is less than critical value, all into step S1.12.Wherein,In step S1.12, it is assumed that the first battery core 13 has reached the second transition voltage T2 and the second battery core 14 not yet reaches second turnState voltage T2, now makes it switch to closed circuit state on the switch 121 for the balancing circuitry 12 for turning on the first battery core 13, and others are put downThe circuit 12 that weighs is then open-circuit condition, and adjust the current value of charging current, makes it equal to the first battery core 13 of high voltageCalculated value obtained by magnitude of voltage (i.e. the second transition voltage T2) divided by the resistance value of dead resistance 122.Now, the first battery core 13Electric energy will be consumed resistance 122 because of the conducting of switch 121 and be consumed so that the magnitude of voltage of the first battery core 13 will be maintained at theTwo transition voltage T2, the magnitude of voltage of the second battery core 14 then persistently rise.
Enter step S1.13 afterwards, measure the magnitude of voltage of the first battery core 13 and the second battery core 14, and enter step S1.14Judge whether the difference of the magnitude of voltage of the first battery core 13 and the second battery core 14 is equal to 0, step is returned to if difference is not equal to 0S1.12, step S1.13 and S1.14 are repeated afterwards, until the first battery core 13 and the difference of the magnitude of voltage of the second battery core 14 are equal to0th, i.e. both magnitudes of voltage just enter step S1.15 after all reaching the second transition voltage T2.
In step S1.15, microcontroller 10 will control charger 30 to be charged with constant voltage mode III, in this realityApply in example, the current value of charging current will decline (such as Fig. 3).Perform step S1.16 again afterwards, measure the first battery core 13 and theThe magnitude of voltage of two battery cores 14, and enter in step S1.17 and judge whether the first battery core 13 or the second battery core 14 have any one to reachTo blanking voltage.If the first battery core 13 or 14 none of battery core of the second battery core reach blanking voltage, repeatStep S1.15 to step S1.17.On the contrary then microcontroller 20 controls charger 30 to stop charging (step S1.18), avoids battery10 overcharge and cause danger.
In embodiment more than, once microcontroller 20 finds that the difference DELTA V of voltage between each battery core is excessive, you can it is logicalCross and control balancing circuitry 12 corresponding with the battery core with maximum voltage value for closed circuit state, and adjust the electric current of charging currentValue, and the voltage for the battery core for making to have maximum voltage value maintains fixed value, and continue to increase the magnitude of voltage of other battery cores, fromAnd the charged state of balanced each battery core.
Fig. 4 is the battery module data as a control group using traditional charging method, it can be seen that enteringAfter fast charge pattern II, the voltage difference Δ V between battery core gradually expands so that and both charged states have notable difference, andDeep charge can not be carried out to whole rechargeable battery.Consequently, it is possible to after after multiple discharge and recharge, if there is part alwaysBattery core by deep charge, can not may cause the life-span of rechargeable battery 10 to be shortened.
It should be noted that in charging process, there is the battery core of maximum voltage value and the battery core of minimum amount of voltage that to be possible toUnusual fluctuation occurs at different time points, therefore should not be limited to by the present embodiment.
Finally it is to be emphasized again that the implementation steps disclosed in the above embodiment of the present invention, by way of example only, notFor limiting scope of the present application, other possible alternate variations should also be included in the scope of patent protection of the application such as.