battery costs accounted for 40 percentage of vehicle cost, or even more, reduce the cost of battery power has been an important task of battery suppliers and OEMs. Pack conventional cell structure, usually by the “cell – Module – whole package” tertiary structures. A plurality of batteries together, referred to as “module”; together a plurality of modules, coupled with the BMS parts, power distribution modules, etc. become “Battery Pack.” This drop-powered battery, one of the principal means is to reduce the cost of “modules”, but now this approach has come to the bottleneck.
both how to reduce battery costs, but also improve the energy density, increase mileage?
CTP technology may be the best choice for the moment!
CTP technology Full Cell To Pack, also called module-free technology, the prior art two different routes. First, the total elimination module program to insert batteries BYD represented; the second is a small module integrated into large modules of programs to Ningde era CTP technology as the representative. In addition, the battery BYD blade specialize iron phosphate lithium battery, nickel ternary Ningde age lithium-based high places.
■ BYD CTP technology What are the characteristics?
BYD blade batteries, is based on the earlier side of the battery, the batteries do “long” to do “thin”, shaped like a blade. The public information display, BYD a total of five batteries of different specifications, specific data in the following table. In fact, the height of such batteries are now compared with no change in the battery case side, thickness of the soft package batteries slightly thicker compared to the length of the major change, both from 435mm up to 2500mm. There, BYD exactly how to do, based on current information is unclear.
This cell will form the battery PACK, will depend CTP technology. In one aspect of this technology to enhance the battery pack PACK space utilization and increase the charge amount; PACK other hand reduce the weight and improve energy density of the entire package.
FIG Patent cell BYD blade
a schematic view of the conventional tertiary structure of the battery PACK
The patent BYD can be seen, in the battery pack coincide with the total volume, the conventional battery pACK structure, a multi-module side plates, end plates, fasteners, beams, etc. stringer assembly, the inner bag space utilization percentage probably about 40; and BYD battery pack using the CTP technology, removing the battery management system, distribution box assembly, the bag space utilization in about 62 percentage. Affected by different cell layout, encapsulated space utilization percentages were 55, 60 percentages, 62 percentage, the percentage of 65, 80 even if demand percentage. Even with the same vehicle, the battery-PACK CTP technology, an increase of about 20 percentage charge percentage -30, mileage can also enhance the percentage of 20 -30 percentage.
■ Ningde era CTP technology any different?
On the last age Ningde Frankfurt motor show, announced partial information its own CTP technology, this battery PACK consists of at least two large modules (see below), each of module inter-connected by a fixing element on the battery tray, fixed to the final battery PACK mounting beam through different models.
Battery Pack Ningde schematic CTP technology era
CTP technology era Ningde exploded view of the battery module
[ 123] according to the patent can be seen Ningde age, which is divided into a large number of modular plastic material into a space of the heat radiating plate of a small, square shells batteries as computer hard drives, as these may be inserted into a small space. Side of each cell is also affixed thermal silica pad, the heat radiating plate and the cell channel width direction of the left heat can be directly
to the External cooling line . The data show, this percentage can be reduced to about 40 parts, of these parts from the connection between the modulesHarness, side panels, floor and so on. Further, in the case of constant volume of the battery, using the CTP technology Pack battery pack 15 also improves the volumetric efficiency percentage -20 percentage.
■ CTP technology What are the advantages?
1 weight. Pack CTP reduce battery internal to the greatest degree in the art, the side panels between the respective module base plate, the wiring harness is connected, fixture, unnecessary beams, longitudinal beams and other parts, for the weight reduction of the battery is very helpful .
CTP technology era Ningde battery module connection
2, to enhance the energy density of the battery. and there are two dimensions, the first one is the weight ratio of the energy density , this argument is also our common; CTP technology to Ningde era, for example, the weight ratio of the energy density can reach 200Wh / kg. The second dimension is the volume energy density , BYD the CTP technology, for example, specific energy density compared to the volume can be increased by 50 percentage past, different specifications of the volume energy density of the cell were 439Wh / L , 448Wh / L, 449 Wh / L, 450 Wh / L.
In contrast, using the CTP technology BYD by weight of lithium iron phosphate Pack specific energy density battery has reached 180Wh / kg, comparable to the current battery-Pack NCM811 the batteries.
Another form of arrangement of the battery BYD blade
3, and low cost. In fact, an important driver of landing CTP technology is to reduce demand for battery power costs. BYD, for example, the cost of the new product can be reduced by 20 percentage -30 percentage. It contains elements of the cost of the battery itself Pack also includes simplifying the production assembly process, the factors leading to poor rate of decline. Ningde era although did not disclose the cost advantage, but because of the positive impact of productivity gains brought by 50 percentage clearly can not be ignored.
■ stage, for CSome doubt TP technology?
1, the battery collision safety. Battery Pack conventional tertiary structure, because of the presence of the module, so that multiple crash safety protection layer. Pack battery using the CTP technology, Pack side beam removed, the cell will be subjected to direct impact of the collision.
from
Existing view information, Ningde Case Age, Pack frame is directly extruded aluminum, to increase the strength; each module inside the large plastic shell body by injection molding, the injection molding die radiator plate embedded in the housing, to achieve integral molding.
CTP Ningde age radiator plate in the battery module schematic art
2, battery thermal management. As the new technology has changed the structure of the battery Pack, it is bound to have a battery thermal management system, even BMS system requirements and proposed a new design strategy, which is the software level considerations.
From a hardware perspective, a new design BYD vent and exhaust passage for such battery Pack. Explosion vent valve against the ends of the batteries, when the flame, smoke or gas from the explosion-proof valve, the exhaust gas will enter through the vent passage is discharged outside the battery pack. Battery Pack conventional similar exhaust passage is not designed, flame, smoke or gas is easily gathered in the module, cause secondary damage to the cell.
BYD blade design cell exhaust passage (explosion-proof valves 103, 221 to vent to the exhaust passage 222)
similar design I in the patent application Ningde times have seen, for a ternary lithium and more heat, the use of each cell Ningde age CTP technology, the built-in upper and lower cases. Between the intermediate housing filled with a thermally conductive glue, cell sidewalls and housing as well as a pressure or temperature sensor. The former is used to detect the change in shape of the cell, which is used to detect temperature variations, troubleshooting cell to advance to the pre-measured cell thermal runaway.
3, Repairs convenience and cost. It is known almost V-proposed Zhu YulongA question – because the batteries or take in some way (perhaps stick) directly fixed to the battery tray Pack, therefore 4S shop maintenance in the future, one of the technology put forward higher requirements, the second is a batteries failure, you may need to replace the entire battery pack.
Still another layout
BYD insert cell
4, the consistency of the battery. There estimation analysis, using the CTP technology batteries, therein perhaps several smaller batteries in a series and a way of connecting. Whether this speculation is correct, this new technology for the consistency of the battery does raise higher requirements. There is also contains two aspects, one is the consistency of the production process of the batteries, the second is the consistency of the battery during use. The consistency of the battery, has always been a good domestic battery manufacturers is difficult to solve the problem.
■ There have someone CTP technology?
In addition to the above Ningde era and BYD, Great Wall Motor’s cellular energy, the country Xuan Tech and other battery companies are developing their own CTP technology.
According to the hive energy sources, both without their CTP technology program module, the module also has a large program. Compared to conventional honeycomb energy module 590, CTP-G1 24 to reduce the percentage of the number of parts, reduce the cost per cell Wh 0.1 yuan; CTP-G2 to enhance the efficiency of group 5 weight percent to -10 percentage, the percentage of 5 to enhance space utilization, to reduce the 22 percentage number of parts, reduce the cost per cell 0.21 yuan Wh / Wh. But there is no more technical information revealed.
CTP hive of new energy battery display
On the other hand, in March this year, BYD will be officially released “Super lithium iron phosphate batteries,” BYD will the CTP technology may have more information. Beiqi new energy is determined to be in the EU5, the first to carry a battery Ningde using CTP technology era, we can look forward to. According to the OEM battery testing process is expected to end this year Q1, we will see more use of battery technology CTP technology publication highlights.
■ state review
CTP technology to significantly improve battery energy density, raise pure electric vehicle mileage, which is a good thing for consumers. However, the return of the article title question –CTP technology make our cars safer and cheaper? So far, still a question mark. Safety, the most basic and most important consistency of the battery, domestic battery with battery companies in Japan and South Korea there is a large gap; reduce costs, since the battery supplier will have even more right to speak, new technology has brought the cost of the battery, We have not yet seen whether it can reflect on the guidance of the vehicle.
Of course, we have reason to believe that when the CTP technology has become a trend, we are now fears will no longer be a problem.