CN108987853A - A kind of power battery pack low-temperature heat charging system and charging method - Google Patents

A kind of power battery pack low-temperature heat charging system and charging method Download PDF

Info

Publication number
CN108987853A
CN108987853A CN201810964665.2A CN201810964665A CN108987853A CN 108987853 A CN108987853 A CN 108987853A CN 201810964665 A CN201810964665 A CN 201810964665A CN 108987853 A CN108987853 A CN 108987853A
Authority
CN
China
Prior art keywords
battery pack
power battery
charging
temperature
mould group
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Pending
Application number
CN201810964665.2A
Other languages
Chinese (zh)
Inventor
黄守怀
朱仓颉
刘苏
陈良清
王春波
朱志恒
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Suzhou De Lingxun Power Technology Co Ltd
Original Assignee
Suzhou De Lingxun Power Technology Co Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Suzhou De Lingxun Power Technology Co Ltd filed Critical Suzhou De Lingxun Power Technology Co Ltd
Priority to CN201810964665.2A priority Critical patent/CN108987853A/en
Publication of CN108987853A publication Critical patent/CN108987853A/en
Pending legal-status Critical Current

Links

Classifications

    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01MPROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M10/00Secondary cells; Manufacture thereof
    • H01M10/60Heating or cooling; Temperature control
    • H01M10/61Types of temperature control
    • H01M10/615Heating or keeping warm
    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01MPROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M10/00Secondary cells; Manufacture thereof
    • H01M10/42Methods or arrangements for servicing or maintenance of secondary cells or secondary half-cells
    • H01M10/44Methods for charging or discharging
    • H01M10/443Methods for charging or discharging in response to temperature
    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01MPROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M10/00Secondary cells; Manufacture thereof
    • H01M10/60Heating or cooling; Temperature control
    • H01M10/63Control systems
    • H01M10/635Control systems based on ambient temperature
    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01MPROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M10/00Secondary cells; Manufacture thereof
    • H01M10/60Heating or cooling; Temperature control
    • H01M10/65Means for temperature control structurally associated with the cells
    • H01M10/657Means for temperature control structurally associated with the cells by electric or electromagnetic means
    • H02J7/0091
    • YGENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02EREDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
    • Y02E60/00Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
    • Y02E60/10Energy storage using batteries

Landscapes

  • Engineering & Computer Science (AREA)
  • Manufacturing & Machinery (AREA)
  • Chemical & Material Sciences (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Electrochemistry (AREA)
  • General Chemical & Material Sciences (AREA)
  • Automation & Control Theory (AREA)
  • Physics & Mathematics (AREA)
  • Electromagnetism (AREA)
  • Secondary Cells (AREA)
  • Charge And Discharge Circuits For Batteries Or The Like (AREA)

Abstract

The invention proposes a kind of power battery pack low-temperature heat charging system and charging method, by being arranged heating module is spiral inside battery modules and outside is so that the efficiency of heating module heating improves reduces heating time;Meanwhile according to the remaining electricity of the power battery pack, energy source of the power battery pack as heating module preferentially is selected, only when power battery pack not enough power supply, then external charge mould group is accessed and charges to the heating module;Further, it is also possible to which the charging module of the charging module of the power battery pack and the heating module is combined into one, the quantity of charging module has been simplified, can also reduce the cost of low temperature charging to a certain extent.

Description

A kind of power battery pack low-temperature heat charging system and charging method
Technical field
Rechargeable battery field of the present invention, more particularly, to a kind of power battery pack low-temperature heat charging system and charging side Method.
Background technique
Power battery refers to for the power supply in powered tools source, be applied to more electric car, electric train, it is electronic from Driving, golf cart etc. provide the battery of power as it.According to positive and negative pole material different demarcation used, power electric Pond generally comprises zinc series cell, nickel series battery, lead series battery, lithium series battery, manganese dioxide series battery and sky Gas series battery, compared to other series batteries, lithium battery has operating voltage high, and specific energy is high, has extended cycle life, self discharge The advantages that small and feature of environmental protection is high, but its in cryogenic conditions to there is charging slow, or even the problem of can not charge.
To solve the problems, such as the hardly possible that charges under cryogenic conditions, usually by the way that one or heating module are arranged in battery pack, Heating module is usually attached to the side or two sides of battery pack, is heated by way of heat transfer for battery pack, heat efficiency Difference, the time is long, and the controllability of temperature is low;In addition, in addition to the charging unit for laying battery pack, it is also necessary to additionally install heating module additional Charging unit, lay complicated, low temperature charging cost is higher.
Summary of the invention
To solve the above problems, the invention proposes a kind of power battery pack low-temperature heat charging system and charging methods.
Main contents of the invention include:
A kind of power battery pack low-temperature heat charging system, including power battery pack, heating module, parameter detecting mould group, Charging module and controller;
The power battery pack is connected by first switch mould group with the heating module;The charging module is led to respectively It crosses second switch mould group and third switching molding group is connected with the heating module and the power battery pack;
The controller controls the first switch mould group, the on-off of second switch mould group and third switching molding group;Work as institute The temperature and electricity while when being less than its corresponding setting value of power battery pack are stated, the controller controls the second switch mould Group conducting, provides the energy using the charging module for the heating module;When the electricity of the power battery pack is not less than it Setting value, and when at a temperature below its setting value, the controller controls the first switch mould group conducting, uses the power Battery pack provides energy source for the heating module;When the temperature of the power battery pack is higher than its setting value, the control Device processed controls the third switching molding group conducting, the use of the charging module is power battery pack charging;
The parameter detecting mould group is connected with the controller and the power battery pack, for detecting the power electric The state of pond group;
The heating module is twist arranged for heating for the power battery pack.
Preferably, the heating module is heating sheet, heating film and heating plate;The heating module includes vertical section and water Flat section, the vertical section are arranged inside the power battery pack, and the horizontal segment is arranged outside the power battery pack end Side.
Preferably, the power battery pack includes several battery units, and the battery unit is arranged successively, and adjacent two The battery unit is one group;The vertical section of the heating module is arranged between the battery unit of two adjacent groups, described The horizontal segment of heating module be arranged in every group described in battery unit end.
Preferably, the parameter detecting mould group includes electric power detection unit and temperature detecting unit, the electric power detection list Member is for measuring the state of charge of the power battery pack;The temperature detecting unit is for detecting the power battery pack and institute State the state of temperature of heating sheet mould group.
Preferably, the electric power detection unit is electric power detection chip;The temperature detecting unit is multiple temperature sensing Device.
Preferably, the charging module includes that multiple electric current output sub-interfaces and an electric current export total interface, the electricity Stream exports total interface and connect respectively with the power battery pack and the heating module;Multiple electric current output sub-interfaces pass through Charge switch exports total interface with the electric current and connect.
Preferably, the first switch mould group, second switch mould group and third switching molding group are relay or electronics Switch.
The invention also provides the charging methods based on above-mentioned power battery pack low-temperature heat charging system, including walk as follows It is rapid:
S1. the temperature of power battery pack is obtained;When the temperature of the power battery pack is higher than its setting value, the controller The third switching molding group conducting is controlled, the charging module power battery pack charging is made;When the power battery pack Temperature be lower than its setting value, then perform the next step;
S2. the electricity of power battery pack is obtained;When the electricity of the power battery pack is not less than its setting value, the control Device processed controls the first switch conducting and provides energy source so that the power battery pack is discharged for the heating module;When When the electricity of the power battery pack is lower than its setting value, the controller controls the second switch mould group conducting, makes described Charging module provides energy source for the heating module.
The beneficial effects of the present invention are: the invention proposes a kind of power battery pack low-temperature heat charging system and chargings Method, by being arranged heating module is spiral inside battery modules and outside, so that the efficiency of heating module heating mentions Height reduces heating time;Meanwhile according to the remaining electricity of the power battery pack, preferentially select power battery pack as adding The energy source of thermal module, only when power battery pack not enough power supply, then access external charge mould group to the heating module into Row charging;Further, it is also possible to the charging module of the charging module of the power battery pack and the heating module is combined into one, The quantity of charging module has been simplified, can also reduce the cost of low temperature charging to a certain extent.
Detailed description of the invention
Fig. 1 is overall structure diagram of the invention;
Fig. 2 is the structural schematic diagram of heating module of the present invention setting.
Specific embodiment
The technical solution protected below in conjunction with attached drawing to the present invention illustrates.
Fig. 1 is please referred to Fig. 2.As shown in Figure 1, the invention proposes a kind of power battery pack low-temperature heat charging system, Including power battery pack 2, heating module 1 and parameter detecting mould group, charging module and controller, wherein the heating module Be tightly attached to the outside of the power battery pack 2, specifically, as shown in Fig. 2, the heating module 1 is twist arranged, for for The power battery pack 2 heats, and in the present embodiment, the heating module 1 includes vertical section 11 and horizontal segment 12, wherein institute The inside that vertical section 11 is located at the power battery pack 2 is stated, the end of the power battery pack 2 is arranged in the horizontal segment 12; The power battery pack 2 includes several battery units 20 being arranged successively in one of the embodiments,;The battery unit 20 It include the battery of several longitudinal arrangements, several battery units 20 are transversely arranged;The heating module includes several heating Unit, as shown in Fig. 2, several heating units are L-shaped, adjacent battery is arranged in the vertical section 11 of the heating unit Between unit 20, and the end of battery unit 20 is arranged in the horizontal segment 12 of the heating unit;Further, adjacent two A battery unit 20 is one group, and the battery list of the two adjacent groups is arranged in the vertical section 11 of the heating module 1 Member 20 between, and its horizontal segment 12 be then arranged in every group described in battery unit end.
The heating module 1 transmits heat to the power battery pack 2 in the form of heat radiation in one of the embodiments, Amount keeps the power battery pack 2 heated more evenly;The heating module 1 can be heating sheet, in heating film or heating plate It is a kind of.
The energy source of the heating module can generally be provided by the charging module outside power battery pack, at this In invention, the energy source of the heating module is provided by the power battery pack first, specifically, the electricity of the heating module Source input interface is connected with the power output interface of the power battery pack by first switch mould group;Meanwhile the heated mould The power input interface of group also passes through second switch mould group and is connected with charging module;The controller is opened for controlling described first The opening and closing of Guan Mo group and the second switch mould group;When the parameter detecting mould group detect the power battery pack electricity and When temperature is less than its corresponding setting value simultaneously, the controller controls the second switch mould group conducting, is by charging module The heating module provides energy source, can be the power battery pack heating;And when the parameter detecting mould group is examined The temperature of the power battery pack is measured lower than its setting value, and the electricity of the power battery pack is set not less than its electricity Value, the controller controls the first switch mould group conducting, so that the power battery pack provides energy for the heating module Measure source;When the temperature of the power battery pack reaches chargeable temperature, controller controls the power battery pack or fills Electric mould group stops providing energy source for the heating module, then starts to charge for power battery pack.
In order to further simplify structure, by the heating module set of the charging module of power battery pack and the heating module In a charging module, specifically, the charging module includes that multiple electric current output sub-interfaces and an electric current output are total Interface, the electric current exports total interface and is connected respectively with the power battery pack and the heating module, and multiple electricity Stream output sub-interface exports total interface with the electric current by charge switch and connect;Meanwhile in the power battery pack and described Third switching molding group is provided between charging module, when the temperature of the power battery pack is not less than setting value, the control Device can control the third switching molding group to be connected, and make the charging module power battery pack charging;Each electricity Stream output sub-interface exports the selection that total interface is connected with the electric current and is determined by the controller, when charging module needs for institute When stating heating module charging, controller selects corresponding electric current output sub-interface and the electric current to export the charging between total interface Switch conduction, meanwhile, the second switch mould group is connected;The output electric current of i.e. different electric current output sub-interfaces is different;? In one embodiment, the quantity of electric current output sub-interface can be 2, a corresponding heating module, a corresponding power Battery pack;In other embodiments, the quantity of electric current output sub-interface can be multiple, it can be divided into two groups, one group of correspondence Heating module, one group of corresponding power battery pack, and the interface including multiple and different output electric currents in every group, to increase charging module Versatility.
It the first switch mould group in one of the embodiments, second switch mould group and third switching molding group and fills Electric switch is the electronic switches such as relay or MOSFET.
The parameter detecting mould group includes electric power detection unit and temperature detecting unit, institute in one of the embodiments, Electric power detection unit is stated for measuring the state of charge of the power battery pack;The temperature detecting unit is described dynamic for detecting The state of temperature of power battery pack and the heating sheet mould group;Preferably, the electric power detection unit is electric power detection chip;It is described Temperature detecting unit is multiple temperature sensors.
The invention also provides the charging methods based on above-mentioned power battery pack low-temperature heat charging system, including walk as follows It is rapid:
S1. the temperature of power battery pack is obtained;When the temperature of the power battery pack is higher than its setting value, the controller The third switching molding group conducting is controlled, the charging module power battery pack charging is made;When the power battery pack Temperature be lower than its setting value, then perform the next step;
S2. the electricity of power battery pack is obtained;When the electricity of the power battery pack is not less than its setting value, the control Device processed controls the first switch conducting and provides energy source so that the power battery pack is discharged for the heating module;When When the electricity of the power battery pack is lower than its setting value, the controller controls the second switch mould group conducting, makes described Charging module provides energy source for the heating module.
It is described after the temperature of the power battery pack reaches chargeable temperature after the heating of the heating module Controller controls the third switching molding group conducting, so that the charging module is power battery pack charging.
The above description is only an embodiment of the present invention, is not intended to limit the scope of the invention, all to utilize this hair Equivalent structure or equivalent flow shift made by bright specification and accompanying drawing content is applied directly or indirectly in other relevant skills Art field, is included within the scope of the present invention.

Claims (8)

1. a kind of power battery pack low-temperature heat charging system, which is characterized in that including power battery pack, heating module, parameter Detect mould group, charging module and controller;
The power battery pack is connected by first switch mould group with the heating module;The charging module passes through respectively Two switching molding groups and third switching molding group are connected with the heating module and the power battery pack;
The controller controls the first switch mould group, the on-off of second switch mould group and third switching molding group;When described dynamic When the temperature and electricity of power battery pack are less than its corresponding setting value simultaneously, the controller controls the second switch mould group and leads It is logical, the energy is provided using the charging module for the heating module;When the electricity of the power battery pack is not less than its setting Value, and when at a temperature below its setting value, the controller controls the first switch mould group conducting, uses the power battery Group provides energy source for the heating module;When the temperature of the power battery pack is higher than its setting value, the controller The third switching molding group conducting is controlled, the use of the charging module is power battery pack charging;
The parameter detecting mould group is connected with the controller and the power battery pack, for detecting the power battery pack State;
The heating module is twist arranged, for heating for the power battery pack.
2. a kind of power battery pack low-temperature heat charging system according to claim 1, which is characterized in that the heated mould Group is heating sheet, heating film and heating plate;The heating module includes vertical section and horizontal segment, and the vertical section is arranged described Inside power battery pack, the horizontal segment is arranged on the outside of the power battery pack end.
3. a kind of power battery pack low-temperature heat charging system according to claim 2, which is characterized in that the power electric Pond group includes several battery units, and the battery unit is arranged successively, and two adjacent battery units are one group;It is described to add The vertical section of thermal module is arranged between the battery unit of two adjacent groups, and the horizontal segment of the heating module is arranged at every group The end of the battery unit.
4. a kind of power battery pack low-temperature heat charging system according to claim 1, which is characterized in that the parameter inspection Surveying mould group includes electric power detection unit and temperature detecting unit, and the electric power detection unit is for measuring the power battery pack State of charge;The temperature detecting unit is used to detect the state of temperature of the power battery pack and the heating sheet mould group.
5. a kind of power battery pack low-temperature heat charging system according to claim 4, which is characterized in that the electricity inspection Survey unit is electric power detection chip;The temperature detecting unit is multiple temperature sensors.
6. a kind of power battery pack low-temperature heat charging system according to claim 1, which is characterized in that the charging mould Group includes multiple electric currents output sub-interface and electric current exports total interface, the electric current export total interface respectively with the power Battery pack is connected with the heating module;Multiple electric current output sub-interfaces are always connect by charge switch and electric current output Mouth connection.
7. a kind of power battery pack low-temperature heat charging system according to claim 1, which is characterized in that described first opens Guan Mo group, second switch mould group and third switching molding group are relay or electronic switch.
8. a kind of charging method of power battery pack low temperature charging system as described in claim 1 to 7 is any, feature exist In including the following steps:
S1. the temperature of power battery pack is obtained;When the temperature of the power battery pack is higher than its setting value, the controller control The third switching molding group conducting makes the charging module power battery pack charging;When the temperature of the power battery pack Degree is lower than its setting value, then performs the next step;
S2. the electricity of power battery pack is obtained;When the electricity of the power battery pack is not less than its setting value, the controller It controls the first switch conducting and provides energy source so that the power battery pack is discharged for the heating module;When described When the electricity of power battery pack is lower than its setting value, the controller controls the second switch mould group conducting, makes the charging Mould group provides energy source for the heating module.
CN201810964665.2A 2018-08-23 2018-08-23 A kind of power battery pack low-temperature heat charging system and charging method Pending CN108987853A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN201810964665.2A CN108987853A (en) 2018-08-23 2018-08-23 A kind of power battery pack low-temperature heat charging system and charging method

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN201810964665.2A CN108987853A (en) 2018-08-23 2018-08-23 A kind of power battery pack low-temperature heat charging system and charging method

Publications (1)

Publication Number Publication Date
CN108987853A true CN108987853A (en) 2018-12-11

Family

ID=64547242

Family Applications (1)

Application Number Title Priority Date Filing Date
CN201810964665.2A Pending CN108987853A (en) 2018-08-23 2018-08-23 A kind of power battery pack low-temperature heat charging system and charging method

Country Status (1)

Country Link
CN (1) CN108987853A (en)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2022016871A1 (en) * 2020-07-20 2022-01-27 广州汽车集团股份有限公司 Battery heating system, battery device and electric vehicle

Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH10284133A (en) * 1997-04-08 1998-10-23 Sony Corp Battery pack and its charging method
CN102324590A (en) * 2011-04-29 2012-01-18 华南师范大学 Temperature controlling system and method used during lithium ion power battery pack charging or discharging procedure
CN104409785A (en) * 2014-11-27 2015-03-11 苏州贝多环保技术有限公司 Electric vehicle battery management system and management method
CN105553012A (en) * 2015-12-31 2016-05-04 惠州市亿能电子有限公司 Low-temperature charging control system and control method
US20170008419A1 (en) * 2015-07-08 2017-01-12 Atieva, Inc. Method and Apparatus for Selectively Heating Individual Battery Modules Within a Battery Pack
CN107953795A (en) * 2017-12-05 2018-04-24 上海航天电源技术有限责任公司 A kind of power battery pack low-temperature charging method
CN209119278U (en) * 2018-08-23 2019-07-16 苏州德凌迅动力科技有限公司 A kind of power battery pack low-temperature heat charging system

Patent Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH10284133A (en) * 1997-04-08 1998-10-23 Sony Corp Battery pack and its charging method
CN102324590A (en) * 2011-04-29 2012-01-18 华南师范大学 Temperature controlling system and method used during lithium ion power battery pack charging or discharging procedure
CN104409785A (en) * 2014-11-27 2015-03-11 苏州贝多环保技术有限公司 Electric vehicle battery management system and management method
US20170008419A1 (en) * 2015-07-08 2017-01-12 Atieva, Inc. Method and Apparatus for Selectively Heating Individual Battery Modules Within a Battery Pack
CN105553012A (en) * 2015-12-31 2016-05-04 惠州市亿能电子有限公司 Low-temperature charging control system and control method
CN107953795A (en) * 2017-12-05 2018-04-24 上海航天电源技术有限责任公司 A kind of power battery pack low-temperature charging method
CN209119278U (en) * 2018-08-23 2019-07-16 苏州德凌迅动力科技有限公司 A kind of power battery pack low-temperature heat charging system

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2022016871A1 (en) * 2020-07-20 2022-01-27 广州汽车集团股份有限公司 Battery heating system, battery device and electric vehicle

Similar Documents

Publication Publication Date Title
CN104682485B (en) Battery charge controller
CN101246976B (en) Lead acid accumulator charging method and charger thereof
CN104145399B (en) Battery control system and set of cells
CN209119278U (en) A kind of power battery pack low-temperature heat charging system
CN103475041B (en) The battery charging controller and method of electric automobile
CN201323466Y (en) Single battery charger adopting an SCM to conduct safety control
CN104868566B (en) A kind of controller for solar and solar recharging system
CN106129527A (en) A kind of Li-ion batteries piles lug liquid cooling apparatus cold based on liquid
CN202663151U (en) Quick charge system for lead-acid storage batteries in photovoltaic system
CN203521558U (en) Low-temperature controlling device of hybrid vehicle battery system
CN110085947A (en) A kind of quick self-heating method of battery cell, system and device
CN104270086B (en) A kind of energy management control circuit of multifunctional light photovoltaic generating system
CN107192965A (en) A kind of dc source aging testing system and its method
CN104253475B (en) Off-grid photovoltaic VRLAB (Valve Regulated Lead Acid Battery) energy storage control device and working method thereof
CN104283490B (en) One kind interruption power termination angle of solar battery system and its performance prediction method
CN115085327A (en) Energy storage device operation control system and method in low-temperature environment
CN201528214U (en) Intelligent pulse charging circuit
CN201267041Y (en) Emergency illuminator
CN101704359A (en) Electric car charger
CN107342442A (en) A kind of battery pack non-dissipative equalizing circuit based on circuit of reversed excitation
CN108987853A (en) A kind of power battery pack low-temperature heat charging system and charging method
CN106685012A (en) Charging control system of lithium battery and working method of charging control system
CN107546809B (en) Intelligent charging system and method based on strain, temperature and voltage regulation
CN202111196U (en) Battery pack with temperature sensing switch
CN103441547A (en) Charger and electric moped with same

Legal Events

Date Code Title Description
PB01 Publication
PB01 Publication
SE01 Entry into force of request for substantive examination
SE01 Entry into force of request for substantive examination