|- -- HMHO -; mmmmrb |] |( ......
`
`
`
`
`
`
`
`| | - mmmmm1 | | | .......... | .......... | .......... | | .......... | .......... | | .......... | | | ..........
`
`
`
`
`
`
`| | | | .......... | .......... | | | .......... | | | .......... | .......... | ..........
`’’’
`..........
`- - .......... .......... ..........
`
`
`..........
`
`.......... ..........
`HHHU
`
`ttttt
`EEEEEEEE
`
`mmmmmmA叶
`
`B
`--
`
`/O
`
`mmmmmmu3
`
`。υ
`
`(10) Patent No.:
`(45) Date of Patent:
`
`US 6,204,641 Bl
`*Mar.20,2001
`
`10/1998 Patino …………………............. 320/150
`5『825『 159
`3/1999 Ito
`..... ..... ..... ..... ..... ..... 320/150
`5:886:527
`6/1999 Grabon
`..... ..... ..... ..... ..... 320/150
`5:912:547
`6,011,379 • 2/1999 Singh et al.
`......................... 320/132
`6;015;347 * 2/1999 Sakakibara
`..... ..... ..... ..... 320/150
`
`FOREIGN PATENT DOCUMENTS
`0621990 * 12/1992 (DE) ......................….......….. 320/150
`0 746 895
`9/1994 (EP) ........................... H02J/7/04
`0 621 990
`6/1996 (EP) ................................. H02J/7/04
`5-244729
`9/1993 (JP) ............................ H02F/7/10
`Wo 93/19496
`9/1993 (J的…........................... HOlM/10/44
`7 502860
`3/1995 (JP) .............................. HOlM/10/44
`2599333
`4/1997 (JP) ............................ H02J/7/10
`10 14125
`1/1998 (J的…............................... H02J/7/10
`
`本 cited by examiner
`
`Primary Examiner-Peter S. Wong
`Assistant Examiner-Pia Tibbits
`(74) Attorney, Agent, or Firm-Sughrue, Mion, Zinn,
`Ma叩巳ak & Seas, PLLC
`
`(57)
`
`ABSTRACT
`
`A battery charger and a charging method capable of charging
`a battery for a short period of time while suppressing the
`battery temperature from rising, by incorporating in the
`battery charger memory a look-up table for mapping an
`allowable value of current with which the battery can be
`charged based on a battery temperature and a battery tem(cid:173)
`perature rise only. The current temperature of the battery is
`detected (in step Sl2) and a temperature rise is calculated
`from the detected temperature (in step Sl4). An allowable
`current map is then retrieved from the detected temperature
`and the obtained temperature rise, an allowable current with
`which the battery can be charged while suppressing battery
`temperature from rising is obtained (in step Sl6) and the
`battery is charged with the allowable current (in step S20).
`Since the allowable current which the battery can be charged
`with, while suppressing battery temperature from rising is
`retrieved using the map which the allowable current is
`mapped, based on battery temperature and battery tempera(cid:173)
`ture rise, and charging current is controlled, it is possible to
`charge the battery for a short period of time while suppress(cid:173)
`ing battery temperature from rising.
`
`6 Claims, 6 Drawing Sheets
`
`(12) United States Patent
`Sakakibara
`
`(54) BATTERY CHARGER AND CHARGING
`METHOD
`
`(75)
`
`Inventor: Kazuyuki Sakakibara, Aichi-Ken (JP)
`
`(73) Assignee: Makita Corporation, Aich比巳n (JP)
`
`( * ) Notice:
`
`Subject to any disclaimer, the term of this
`patent is extended or adjusted under 35
`U.S.C. 154(b) by 0 days.
`
`This patent is subject to a terminal dis(cid:173)
`claimer.
`
`(21) Appl. No.: 09/531,596
`
`(22) Filed:
`
`Mar. 20, 2000
`
`Related U.S. Application Data
`
`(63) Continuation of application No. 09尼58,140, filed on Feb.
`26, 1999, now Pat. No. 5,075,347.
`
`(30)
`
`Foreign Application Priority Data
`
`Feb. 28, 1998
`
`(JP) ...
`
`...
`
`....
`
`...
`
`...
`
`...
`
`...
`
`...
`
`10-64736
`
`Int. CI.7 ........................................................ H02J 7/04
`(51)
`σ勾 U.S. Cl. ……….................................... 320/153; 320/150
`(58) Field of Search ...........….......….............. 320/150, 153
`
`(56)
`
`References Cited
`
`U.S. PATENT DOCUMENTS
`11/1975 Sherman, Jr. …..................... 320/150
`11/1994 Miller et al. ......................... 320/115
`万1996 Yuen
`...
`...
`...
`...
`...
`.. 320/150
`万1996 Koenck et ai. ….........…....... 320/152
`3/1996 Shiojima
`....................... 320/150
`5/1996 Goedken et al. ………........... 320/150
`8/1996 Bohne et al. ........................ 320/160
`10/1996 McClure
`....................... 320/151
`12/1996 Simmonds et al. ........…....... 320/151
`7/1997 Kadouchi et al. .... ...... ..... 320/150
`8/1997 Sanchez et al. ..................... 320/150
`9/1997 Hancock et al.
`..... ..... ..... 320/160
`11/1997 Lutz
`...
`...
`...
`...
`...
`.. 320/110
`2/1998 Grabon ........…...................... 320/150
`4/1998 Le Van Suu .... ..... ..... ..... 320/150
`6/1998 Farley .................................. 320/150
`
`ov－－二AVOYGO句、U句、U♂AV－－ Aυoy－－ GO句、U句、uoy
`oy句3 句30y ♂AVAυr30y句／Aυ句3 ♂AVAυ11句／r3
`0YAυGOt－ Aυ句、UA斗 A斗。or3丁，“A斗。。句30y 乐。
`
`叮／句、UOY句、u句／OYAυ句、U句、u丁，“OYGO乐。哼／OY句／
`ti 二AVGOOYOY－－ r飞〕二AVGOF飞〕r飞〕二AVGOt－句、U♂AV
`OY句3A斗 A斗 A斗 r3r3r3r3乐。乐。乐。乐。哼／哼／哼／
`
`句、ur飞〕r飞〕r飞〕r飞〕r飞〕r飞〕r飞〕r飞〕r飞〕r飞〕r飞〕r飞〕r飞〕r飞〕r飞〕
`
`
`
`9999999999999999 9999999999999999
`
`IT I
`
`~ Tt I 飞1T2I T3T31 T]T41 T4 ~
`
`~ X 1
`
`dT/dtlXt ~ X2
`
`X2 ~
`
`Apple v. Uniloc
`
`Page 1 of 12
`
`Apple Ex. 1006
`
`

`

`U.S. Patent
`
`Mar. 20, 2001
`
`Sheet 1 of 6
`
`US 6,204,641 B1
`
`Fig, |
`
`mu
`
`14
`
`1
`
`16
`
`Apple v. Uniloc
`
`Page 2 of 2
`
`Apple Ex. 1006
`
`Apple v. Uniloc
`
`Page 2 of 2
`
`Apple Ex. 1006
`
`

`

`U.S. Patent
`
`Mar. 20, 2001
`
`Sheet 2 of 6
`
`US 6,204,641 Bl
`
`Fig. 2
`
`t3
`
`m飞
`
`56
`
`3
`
`6 7
`
`时刊了
`
`OQ三
`
`Apple v. Uniloc
`
`Page 3 of 12
`
`Apple Ex. 1006
`
`

`

`U.S. Patent
`
`Mar. 20, 2001
`
`Sheet 3 of 6
`
`US 6,204,641 Bl
`
`Fig. 4
`
`50
`CHARGING i l BATTERY
`I
`CIRCUIT ii
`PACK
`
`l
`
`10
`
`3.2
`
`3,0
`
`B厅干ERYVB
`
`56
`TEMPERATURE!
`j
`.J SENSOR
`
`FO
`
`rM 川
`
`pu ME
`M
`I
`QU
`
`门υTiT
`
`户··u
`
`LN
`-6
`
`00 「3
`
`町，、， P·a·－－
`
`Tl↑l 寸
`M川俨LV－
`OE 一
`
`户－vqu一
`
`34
`HARGING
`CURRENT
`CONTROL
`SECTION
`
`w14CVT
`fTL
`
`R 飞’ TI－－
`E 川ιU二
`
`（UH川 Dnuu－
`Dl 叫扎 Tl＆－
`
`li －－飞i
`
`QV
`
`」 3
`
`〈队产LV一 C
`
`38
`
`TEMPERATURE
`DETECTION
`SECTION
`
`－…··－－－一一－…………·一…... ,
`
`Apple v. Uniloc
`
`Page 4 of 12
`
`Apple Ex. 1006
`
`

`

`U.S. Patent
`
`Mar.20,2001
`
`Sheet 4 of 6
`
`US 6,204,641 Bl
`
`Fig. 5
`
`IT I
`
`T2
`~ T 1 IT 1
`I
`T3
`~ T2 ~ T3 ~ T4 T4 ~
`
`~ X 1
`
`I 12
`(1 )(3)
`
`I 1 3
`(4)
`
`I 1 4
`(Q)
`
`dT/dt IX1 ~ X2 I
`
`I 23
`I 22
`(2) (5)(7)
`
`X2 ~
`
`Apple v. Uniloc
`
`Page 5 of 12
`
`Apple Ex. 1006
`
`

`

`U.S. Patent
`
`Mar.20,2001
`
`Sheet 5 of 6
`
`US 6,204,641 Bl
`
`0
`F』
`
`（三）
`
`ME一←
`
`00
`
`。z一。但〈Zυ
`
`0的
`
`。 叮
`
`。σ
`
`）
`
`。 队
`
`l
`
`0
`...-
`
`。
`
`。
`叶. .....i
`
`斗• .........＞，飞
`
`也-1-.>\
`
`ω’1
`
`毕’气
`
`1
`
`。
`.o·
`
`。－m …’比
`
`_g ..... J
`
`A
`
`1
`
`S夺与」＼ l
`<O
`~）
`~·叫＼
`巳~
`'
`\
`...:.
`\
`v飞J
`υ.... ，－…··气~－－－－二·：；.；.－.·：~－－－…·………＋…－＼－……M ……··占…f……………··
`\ i
`I 立··～~ \
`J
`咽....／
`。＼～－ \
`i
`j
`i
`-0
`·· ..庐.J-' \
`\ !
`A二千X \I
`
`－．〉．飞 v －.. λ
`v
`
`．、
`j:)
`
`~ -0
`
`···.'\.
`
`A的 V
`
`A
`
`、r
`
`叮
`（：））」.N3 滔滔 n:>
`
`队l
`σ）
`。 N I~ 吕VH:>
`
`…唱
`
`0
`(\J
`
`0 …4
`
`。
`
`0
`l.D
`人剖 3.L.LV8
`
`。 可
`
`。σ
`
`3
`
`0
`0
`0
`)
`∞卜 <O
`( J.) 3 剖 n.Lv剖 3dW3J.
`
`。Q
`
`Apple v. Uniloc
`
`Page 6 of 12
`
`Apple Ex. 1006
`
`

`

`U.S. Patent
`
`Mar.20,2001
`
`Sheet 6 of 6
`
`US 6,204,641 Bl
`
`Fig. 7
`
`START
`
`INPUT BATTERY
`TEMPERATURE ITI
`
`S12
`
`S14
`
`CALCULATE BATTERY
`TEMPERATURE DIFFERENCE dT/dt
`
`S16
`SELECT OPTIMUM CHARGING
`CURRENT FROM MAP
`
`S18
`
`No
`
`Low
`
`S20
`CONTINUE TO OUTPUT
`OPTIMUM CHARGING
`CURRENT AND TO
`CHARGE B.r\TTERY
`
`HOW
`ROBABL Y IS CURRENT I
`FINAL CHARGING
`REGIONS?
`
`S24
`
`COMPLETE
`CHARGING
`
`END
`
`Apple v. Uniloc
`
`Page 7 of 12
`
`Apple Ex. 1006
`
`

`

`US 6,204,641 Bl
`
`1
`BATTERY CHARGER AND CHARGING
`METHOD
`
`This is a continuation of application Ser. No. 09/258,140
`filed Feb. 26, 1999, now U.S. Pat. No. 5,075,347, the s
`disclosure of which is incorporated herein by reference.
`
`2
`a temperature rise output device for obtaining the tem(cid:173)
`perature rise from the temperature detected by the
`temperature detection device;
`an allowable current retrieval device for retrieving the
`map of the memory device from the temperature
`detected by the temperature detection device and the
`temperature rise outputted from the temperature rise
`output device, and for obtaining the allowable value;
`and
`a charging device for charging the battery with the allow(cid:173)
`able current retrieved by the allowable current retrieval
`device.
`To attain the above object, the battery charger is techni(cid:173)
`cally characterized by comprising:
`a memory for storing a map for mapping an allowable
`value of current, with which a battery can be charged
`while suppressing battery temperature from rising,
`based on a battery temperature and a battery tempera(cid:173)
`ture rise, the map having the allowable current value set
`low when the battery temperature is high and set low
`when the temperature rise is large;
`a temperature detection device for detecting a current
`temperature of the battery;
`a temperature rise output device for obtaining the tem(cid:173)
`perature rise from the temperature detected by the
`temperature detection device;
`an allowable current retrieval device for retrieving the
`map of the memory device from the temperature
`detected by the temperature detection device and the
`temperature rise outputted from the temperature rise
`output device, and for obtaining the allowable value;
`a charging device for charging the battery with the allow(cid:173)
`able current retrieved by the allowable current retrieval
`device;
`a charging completion determination device for determin(cid:173)
`ing that charging is completed based on whether or not
`the temperature detected by the temperature detection
`device and the temperature rise outputted from the
`temperature rise output device belong to a region
`indicating a final cha电1吨 stage (a region in which
`temperature rise is relatively large and relatively low
`allowable current is outputted) on the map of the
`memory device with high frequency; and
`a charging completion device for completing charging
`based on the determination of the charging completion
`determination device that charging is completed.
`To attain the above object, the charging method is tech(cid:173)
`nically characterized by comprising:
`detecting current temperature of a battery;
`obtaining a temperature rise from the detected tempera(cid:173)
`ture;
`retrieving an allowable current map based on battery
`temperature and battery temperature rise, from the
`detected temperature and the obtained temperature rise,
`and obtaining an allowable value of current, with which
`the battery can be charged while suppressing the bat(cid:173)
`tery temperature from rising; and
`charging the battery with the retrieved allowable current.
`To attain the above object, the charging method is tech(cid:173)
`nically characterized by comprising:
`detecting a current temperature of a battery;
`obtaining a temperature rise from the detected tempera(cid:173)
`ture;
`retrieving an allowable current map based on battery
`temperature and battery temperature rise, from the
`
`15
`
`25
`
`BACKGROUND OF THE INVENTION
`1. Field of the Invention
`The present invention relates to a battery charger and a 10
`charging method for charging a battery. The present inven(cid:173)
`tion relates, in particular, to a battery charger and a charging
`method suitable for charging a battery, such as a nickel metal
`hydride battery, which accumulates a large amount of heat
`during charging.
`2. Description of the Related Art
`A charging-type battery which can be repeatedly charged
`is recently used as a power source for a power tool, for
`example. A nickel metal hydride battery is widely used as
`the power tool battery of this type. To charge the battery, a 20
`battery charger for rapidly charging the battery with high
`current is used. That is, while a battery is rapidly charged for
`about 20 minutes and, a power tool can be continuously used
`while replacing a currently used battery with another one
`which has been charged.
`The inventor of the present invention studied ways to
`improve the performance of a power tool by using, as a
`battery, a nickel metal hydride battery. Although the nickel
`metal hydride battery can provide higher capacity than a
`nickel-cadmium battery, a large amount of heat is generated
`during charging. If the battery temperature becomes high 30
`due to the generated heat, the electrodes and separators of
`cells within the battery deteriorate and battery life is short(cid:173)
`ened. Due to this, the nickel metal hydride battery cannot be
`rapidly charged with high current unlike the nickel-cadmium
`battery.
`Furthermore, the nickel metal hydride battery is more
`sensitive to overcharge than the nickel-cadmium battery and
`overcharging makes the battery life shorter. For that reason,
`it is required to avoid overcharging the nickel metal hydride
`battery. As for equipment which does not require battery 40
`replacement, to avoid overcharging the battery, charging
`current and discharging current are integrated and a battery
`is charged based on the integrated value. Thus, the battery
`can be fully charged. In case of charging a battery for
`己quipment such as the above-stated power tool which 45
`requires replacing one battery with another, however, it has
`been difficult to fully charge the battery without overcharg(cid:173)
`ing it.
`
`35
`
`SUMMARY OF THE INVENTION
`The invention has been made to solve the above-stated so
`disadvantages and has an object to provide a battery charger
`and a charging method capable of charging a battery for a
`short period of time while suppressing battery temperature
`from rising.
`The invention has also been made to solve the above- 55
`stated disadvantages and has an object to provide a battery
`charger and a charging method capable of fully charging a
`battery without fear of an overcharge.
`To attain the above object, the battery charger is techni-
`cally characterized by comprising:
`a memory for storing a map for mapping an allowable
`value of current, with which a battery can be charged
`while suppressing battery temperature from rising,
`based on a battery temperature and a battery tempera-
`ture rise;
`a temperature detection device for detecting a current
`temperature of the battery;
`
`65
`
`60
`
`Apple v. Uniloc
`
`Page 8 of 12
`
`Apple Ex. 1006
`
`

`

`US 6,204,641 Bl
`
`3
`detected temperature and the obtained temperature rise,
`and obtaining an allowable value of current with which
`the battery can be charged while suppressing the bat(cid:173)
`tery temperature from rising;
`charging the battery with the retrieved allowable current;
`determining that charging is completed based on whether
`the outputted temperature rise is relatively large and
`whether relatively low allowable current is outputted
`from the map with a high frequency; and
`
`4
`FIG. 6 is a graph showing the change of charging current
`and that of battery temperature both controlled by the
`charging circuit; and
`FIG. 7 is a flow chart showing the charging circuit
`s process.
`
`DESCRIPTION OF THE PREFERRED
`EMBODIMENT
`
`A battery charger and a charging method in one embodi-
`10 ment according to the present invention will be described
`with reference to the accompanying drawings.
`completing charging based on the determination that
`charging is completed.
`The embodiment which explicitly depicts the present
`invention will be described hereinafter with reference to the
`According to the battery charger and charging method,
`charging current is controlled using a map for mapping an
`accompanying drawings.
`allowable value of current with which a battery can be
`FIG. 1 shows a battery charger 10 in one embodiment
`charged while suppressing battery temperature from rising 15
`according to the present invention. FIG. 2 shows a battery
`based on battery temperature and battery temperature rise.
`pack 50 charged by the battery charger. FIG. 3 shows a
`That is, the map is retrieved from the battery temperature
`and temperature rise. The allowable value of current, with
`battery drill 70 driven by the battery pack 50.
`As shown in FIG. 2, the battery pack 50, including a
`which the battery can be charged while suppressing the
`battery temperature from rising, is obtained. The battery is 20 nickel metal hydride battery, consists of a generally cylin-
`charged with the allowable current thus obtained. This
`drical fitted section 52 and a generally prismatic base 56. A
`key-shaped key section 54 is formed on the side surface of
`makes it possible to charge a nickel metal hydride battery,
`the fitted section 52. The first input terminal t1 connected to
`the temperature of which tends to rise during charging, for
`a short period of time without causing deterioration due to
`the cathode of the battery, the second input terminal t2
`temperature rise. Just before charging is completed, the 25 connected to the anode therein and the third terminal t3
`connected to a temperature sensor consisting of a thermistor
`temperature rise of the nickel metal hydride battery is larger
`and the battery is charged with relatively low current,
`are provided on the upper portions of the fitted section 52.
`therefore it is possible to suppress “ overshoot” after the
`As shown in FIG. 1, a fitting hole 12 for fitting the fitted
`completion of charging.
`section 52 of the battery pack 50 is formed at the battery
`According to the battery charger and charging method, 30 charger 10 for charging the battery pack 50. A key way 14
`charging current is controlled using a map for mapping an
`for introducing the key section 54 of the fitted section 52 is
`allowable value of current with which a battery can be
`formed on the sidewall of the fitting hole 12. The fitting hole
`charged while suppressing battery temperature from rising
`12 is integral with a housing 16 which constitutes the battery
`charger 10 and is made from resin. In this embodiment, the
`based on battery temperature and battery temperature rise.
`That is, the map is retrieved from the battery temperature
`key section 54 is provided at the fitted section 52 of the
`and temperature rise. The allowable value of current, with 35 battery pack 50 and the fitted hole 12 of the battery charger
`10 is provided with the key way 14. This thereby prevents
`which the battery can be charged while suppressing the
`the battery pack 50 from being fitted in an incorrect manner.
`battery temperature from rising, is obtained. Consequently,
`the battery is charged w讪 the allowable current thus
`First to third output terminals (not shown) are provided at
`obtained. This makes it possible to charge a nickel metal
`the bottom of the fitting hole 12 to make contact with the first
`hydride battery the temperature of which tends to rise during 40 to third terminals tl, t2 and t3 of the battery pack 50. An
`charging, for a short period of time without causing dete-
`LED lamp 18 is provided on the top of the battery charger
`rioration due to temperature rise. Just before charging is
`10 to indicate that the battery is bemg charg时．
`completed, the temperature rise of the nickel metal hydride
`As shown in FIG. 3, a fitting hole 72 for fitting the fitted
`section 52 of the battery pack 59 is provided in the battery
`battery is larger and the battery is charged with relatively
`low current, therefore it is possible to suppress 飞vershoot” 45 drill 70. Wh已n electric power is supplied from the first and
`second input terminals t1 and t2 of the batter?' pack 50 to the
`after the completion of charging.
`The completion of charging is determined, in particular,
`battery drill 70, a motor (not shown) is dnven to rotate a
`chuck 76. If the battery drill 70 is in use, a plurality of
`based on whether or not a temperature rise is relatively large
`and whether or not relatively low current is outputted from
`batteries which have been charged within the battery pack 50
`the map with high frequency. That is, based on wheth己r or 50 are sequentially used to allow continuous operation. To this
`end, the battery charger 10 in th自己mbodiment is designed
`not temperature rise is large and whether or not the rise is
`large even if charging current is decreased. Due to this, it is
`to be capable of rapidly charging the battery pack 50 in
`possible to full:\'. charge the battery without fear of over-
`approximately 20 minutes.
`FIG. 4 shows the configuration of a control circuit within
`charging and without being influenced by the remaining
`55 th己 battery charger 10. The control circuit 30 consists of a
`battery capacity, temperature and the like.
`temperature detection section 38 for detecting the tempera(cid:173)
`ture of a battery from an output value of a temperature
`sensor (or thermistor) 56 provided at the battery pack 50
`但由， a memory section 39 for storing a current controlling
`map, a control section 34 for obtaining a temperature rise by
`FIG. 2 is a perspective view of a battery pack in the 60 differentiating a temperature value outputted from the tem(cid:173)
`embodiment according to the present invention;
`perature detection section 38, obtaining an allowable current
`FIG. 3 is a perspective view of a battery drill using the
`value with which the battery can be charged while suppress-
`battery pack shown in FIG. 2;
`ing the rise of battery temperature from retrieving the map
`FIG. 4 is a block diagram showing a charging circuit in
`based on the temperature value and the temperature rise, and
`the battery charger shown in FIG. 1;
`65 outputting the allowable current value as a current command
`FIG. 5 is an explanatory view showing the content of a
`value to the charging control section 34, and the charging
`current control section 34 for controlling a power supply
`map held in the charging circuit;
`
`BRIEF DESCRIPTION OF THE DRAWINGS
`
`FIG. 1 is a perspective view of a battery charger in an
`embodiment according to the present invention;
`
`Apple v. Uniloc
`
`Page 9 of 12
`
`Apple Ex. 1006
`
`

`

`US 6,204,641 Bl
`
`……………川剧川……………队…阳叫………………川…日前…叫时川叫川川剧川川……………咄咄叩…叫…
`
`叫则由时叫m 盯hbMmm由 mpmωEcmh山Zrimmvt即伽…γ川四叫“瓜咄cmFU町的mK问pmwmm口VHar江山川趾灿mmb削MMm
`引出 1…tm…ru出…h…山川川叫山川－
`川口中口山川hm乱中…－wLMm叫……阳山川AUPA巾…阳中山叫川市山川出趴
`
`dm叩川剧山MLd♂叫刷出击MytM叫正山时叫出即
`
`MM叫山叫…hf川口…付山
`
`6
`
`川韶山川川吼叫…川叫叫出………
`
`1…～………………制……一……………川…………叫一阳山川川川……
`
`…m
`
`叫………叩……………………………………四川…
`
`mH…川ω…………叫…………吵…………－
`
`……川叩…………
`
`t…
`
`rm叮叮阳山MUM仙儿问UM： ttt川山川出四川U
`MM川口时…山川U且叫川时川川叫…口吼叫何也
`川叩叫中刚出口Emh叫出叫山川口时川咄mMmm…tumm山川…川口出且也U…川口叫叫
`
`mu叫叫出叮山hu叫trrztM川ZZMMm时町山出川拮叫
`
`5
`
`…←……………白山……………
`
`bmwmuf…川一………一…………～……
`
`叮叮叮川时叫罚出阴阳FMM叫阳川叫mumMruu且用川山川川………
`川时削时thm 比dMMmwdm叩怕“创町阳叫町－
`Mmm叫rzrmdzu乱叫MMMM吼叫Mt此间飞dAt…此削mmmhtzhA川口血MMmM出U口时叫M
`叫阳川ZhE阅价－ZEM 泪mbmw阳抽泣扪
`E 吨
`
`D 叫EMMWM叫可咄咄MMrzz 耻
`
`I
`
`山UW帆dhvWMMmtMmmM
`
`rzm扭曲阳此阳市引吭
`M肌dU山川山mHum叫际毗d时也阳出MP川MKM叫mmMK阳创ω 。比MKNdMn由mrk删吨曰“山山川山
`
`mbb 时，imLm－mJ山川－mdmmkkkdm增吨mddmm卧－m民 MKιMh卧dv队km 吨kawd白 ιmhd 时－pmTK 战kkwdmω削ιMM卧叫“mrJ比·吨
`咄咄叫出口哨…川剧mmm叫时山川…川出川川…叩叫川部位日吼叫叫出阳山川何
`由副 d ∞ bcm电mndmsmvudJ剧’t －mscUMh灿kg 叫 ch 出阳刚山m国 mmh 出 twUM严阳、Mmωrood －1 旧 mm时 g民∞ vm油m
`md 阳mμ矶山几山山峦山Md山卢刚盹dk出－MEwmr叫“川 h阳即内战mTmMru…Mm们问削ιMmd曲创UM叫川vMmω刷出kwdMJ
`川机叫：吨叫也叫乱白白吼叫阳刀向
`回叮吹…立即时Mh…t川山山峦ωzmhm 飞币汇们叫MJ叫MUMZ问即出且um叫umwrh川剧rM叫
`
`甲’
`4 』
`
`nuζJnuζJnuζJnuζJnuζJnuζJ
`1i1i
`
`竹马竹马句
`
`3
`
`凶寸
`
`A凶寸
`
`句3A
`
`ζJζJ
`
`／O
`
`／O
`
`Apple v. Uniloc
`
`Page 10 of 12
`
`Apple Ex. 1006
`
`

`

`US 6,204,641 Bl
`
`8
`7
`First, after charging starts, a control section 36 of the
`at which charging is completed (overshoot dO). The over-
`shoot dO causes temperature to rise further as high as 80。 C.
`battery charger (see FIG. 4) adjusts chargi吨 current and
`even after charging is completed, as a result the life of the
`determines whether battery charging is completed in a
`predetermined cycle (here, at 100 seconds’ intervals for the
`nickel metal hydride battery is shortened. According to the
`graph of FIG. 6, since charging starts at 20。 C. and is 5 convenience of description, but actually far shorter intervals
`completed at 80。 C., a t已mp已ratur已 ris已 is 60。 C dt阳
`p已riod. If, th已r已fo吼 cha皂ir
`of th已 nid臼已l rr削al l ydri正
`st已p 512). N已xt, th已 inputted absolute temperature T is
`batt已ry starts at 30。 C., and t已mp已ratur已 ris已s by 60。 C. to
`differentiated and a battery temperature di旺ιrence dT/dt is
`90。 C. or higher, the battery performance greatly deteriorates
`10 calct山ted (in step 514). Based on the absoh出 temperature
`at this point.
`T and the temperature d1旺ιrence dT/dt, an optimum charg-
`Full line <a> indicates a change in charging current in the
`ing current is selected from the map which has been already
`battery charger in the first embodiment according to the
`described with reference to FIG. 5 (in step 516). In this case,
`present invention, whereas full line <b> indicates a change
`in the temperature of nickel metal hydride battery if the
`as indicated in cycle <1>, where the absolute temperature T
`is between Tl and T2 and the temperature difference dT/dt
`battery is charged by the battery charger in this embodiment.
`The battery charger 10 in this embodiment applies relativ己ly 15 is Xl or less, region 112 is selected and relatively high
`low charging current if battery temperature is high and
`current of 4.SC charging current (9A) is applied as indicated
`temperature rise is large. The device 10 applies medium
`by the full line a shown in FIG. 7.
`level charging current if battery temperature is high and
`Thereafter, the control section 36 determines whether
`temperature rise is small. The device 10 applies medium
`current is in final charging regions, i.e., hatched regions I31,
`level charging current if battery temperature is low and 20 I32, I33, I34 and I35 in which temperature rise is large and
`temperature rise is large. The device 10 applies relatively
`in a region I25 in which temperat旧巳 rise is medium level (in
`high charging current if battery temperature is low and
`step 518). In this case，但时已 the current is not in the final
`temperature rise is small. In this way, the battery charger 10
`charging region （“N。” in the Step 518), process returns to
`in this embodiment adjusts current based on the temperature
`the step 512 and control of the charging current continues.
`of the nickel metal hydride battery and its temperature rise. 25 In cycle <2> after more than 100 seconds pass, because a
`relatively high current has been applied in cycle <1> as
`The device 10 starts charging the battery at a temperature of
`20。 C. as shown in the full line <b> while controlling the
`stated above, the temperature difference dT/dt is larger (Xl
`temperature to fall within 50。 C. or less so as not to affect
`to X2) and re~ion I22 is selected, so that medium level
`the battery life. In other words, the device 10 a句usts
`current (3.SC) is selected. Since the medium level current is
`charging current to maximum current while avoiding 3日前lected in the cycle <2>, the temperature d1旺ιrence dT/dt
`exceeding the expected temperature and shortening charging
`turns into Xl or less. In cycle <3>, the region 112 is selected
`time.
`and relatively high charging current is thereby selected once
`As stated above, the battery charger 10 constantly changes
`again.
`As stated above, if charging is continued while current
`charging current in accordance with the battery temperature
`and temperature rise. That is, high current is applied at an
`value is changed in accordance with the absolute tempera-
`initial charging stage, i.e., while battery temperature is low
`ture T and the temperature difference dT/dt, the di旺ιrence
`and temperature rise is small. Relatively low charging
`dT/dt gradually increases. In cycle <6>, as shown in FIG. 5,
`current is applied at a final charging stage, i.e., if battery
`the temperature d1旺ιrence dT/dt exceeds X2 and enters
`temperature is high and temperature rise is large so that
`region I33. In this case, the determination result is Yes in
`temperature rise is kept small just before the completion of
`step 18. That is, current is determined in the final charging
`charging. Specifically, temperature rise is small (or tempera- 40 regions (regions I31, I32, I33, I34, I35 and I25) as stated
`ture rise gradient is small) from a time b’(11 minutes after
`abov已， and it is th已
`probabl已 in th已 final charging r已gions (in st已p 522). It is
`th已 start of charging) just b已for已 th已 compl已tion of charging
`until a time b” at which charging is completed. As a result,
`determined that it is highly probable in the final charging
`temperature rise (overshoot bO) after the completion of
`regions if it enters the final charging regions in three
`charging is small and heat generation during and after 45 consecutive cycles. While the current is decreased in the
`cycle <6>, the absolute temperature Tis between T2 and T3
`charging is suppressed such that temperature rise during and
`after charging is almost as same (approximately 50。 C.) as
`and the temperature difference dT/dt is decreased to Xl to
`that in lC charging indicated by the dotted line f.
`X2 in the next cycle <7>, whereby current is in the region
`Even in lC charging as indicated by the dotted line f, if
`I23. Thus, the determination result as to whether it is highly
`battery temperature at the start of charging is high, for 50 probable that current is in the final charging region is Iρw
`example, if charging is started at a battery temperature of
`in step 522 and the J?rocess ~oes on to step 20 in which
`30。 C., then temperature rises by 30。 C. and reaches 60。 C.
`chargmg continues with a vanable charging current.
`at the completion of charging. In this embodiment, by
`Meanwhile, if current enters region I25 which belongs to
`contrast, current is controlled in accordance with tempera-
`final charging regions in cycle <13>, current enters the
`ture and battery temperature can be limited to up to 50。 C. 55 region I35 which also belongs to the final charging regions
`in the next cycles <14> and <15>. If current enters final
`when chargin!?: is completed. In the case of the power tool
`battery, in particular, where the motor is continuously driven
`charging regions in three consecutive cycles, the determi-
`with high current and capacity is exhausted, it is probable
`nation result as to whether it is high probable that current
`that charging starts when battery temperature is high
`enters a final charging region is High and charging is
`enough. In the battery charger in this embodiment， ιven if a
`completed (in step 524), thereby ending all series of pro-
`nickel metal hydride battery is at such a high temperature it 60 cessmg.
`can charge to the extent that the temperature does not exceed
`In the above-stated example, description has been given
`an expected charging temperature. It is, thus, possible to
`to a case where cycle time is 100 seconds for convenience
`repeatedly use the nickel metal hydride battery for a long
`of description. Due to this, it is det己rmined that it is highly
`period of time.
`probable if current enters final charging regions in three
`Specific processing of the battery charger in this embodi- 65 consecutive cycles. If cycle time is made shorter than a 100
`seconds’ cycle, it is possible to det己rmine that it is high
`ment will be described with reference to FIGS. 5 and 6 as
`well as the flow chart shown in FIG. 7.
`probable that current enters final charging regions using
`
`35
`
`Apple v. Uniloc
`
`Page 11 of 12
`
`Apple Ex. 1006
`
`

`

`US 6,204,641 Bl
`
`10
`The completion of charging is determined, in particular,
`based on whether or not temperature rise is large and
`whether or not temperature rise is large even if the charging
`current is lowered. Due to this, it is possible to fully charge
`the battery without fear of overcharge and without being
`influenced by the remaining battery capacity, temperature
`and the like.
`What is claimed is:
`1. A battery charger comprising:
`
`a memory for storing a map for mapping an allowable
`value of current, with which a battery can be charged
`while suppressing battery temperature from rising,
`based only on a battery temperature and a battery
`temperature rise;
`a temperature detection device for detecting a current
`temperature of the battery;
`a temperature rise output device for obtaining the tem(cid:173)
`perature rise from the temperature detected by said
`temperature detection device;
`an allowable current retrieval device for retrieving the
`map of said memory device from the temperature
`detected by said temperature detection device and the
`
`9
`various methods. For instanc忘， in a 10 seconds’ cycle, it is
`highly probable that current enters the final charging regions
`in eight out of 10 cycles. Alternatively, it can be determined
`that probability is high if current enters the final charging
`regions in eight out of 10 cycles and if current enters the final ζ
`charging regions in five consecutive cycles.
`~
`As described above, the conventional battery charger for
`charging a nickel-cadmium battery detects that charging is
`completed by keeping a current value constant and moni-
`taring one or more of temperature, temperature change,
`voltage and voltage change. In the case of a nickel metal 10
`hydride battery, however, patterns of temperature an