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"wispywood2344" has estimated electric power capacity of Japanese Ministry of Defence-TRDI developed LIB
and Japanese Navy conventional lead-acid battery (LAB) on my blog before.
The diagram above reflect the dimensions of a Japanese conventional LAB for submarine. According to http://blog.livedoor.jp/wispywood2344/archives/54874167.html when housing the unit cells by using this space of the battery depicted to the
full, "it can house the Li-ion battery capacity of 155.52L per group module.
" The "wispywood2344"
goes on to say "When the volumetric energy density of the submarine for a [GS Yuasa] lithium ion cell is that it is equivalent to "LEV50", its value will
be 218Wh / L. Thus, the total capacity per group module will be 33.9kWh." The battery depicted may weigh 770kg (just a small part of what a submarine uses). Also see http://blog.livedoor.jp/wispywood2344/archives/55055062.html
What all this means I cannot claim to know.
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COMMENT
ON LITHIUM-ION BATTERIES (LIBS)
The Japanese Government and private industry have been methodically analysing the performance of Lithium-ion Batteries (LIBs)
intended for use in submarines for more than a decade. LIBs may be the technology area that Japan has the greatest lead over its French (DCNS) and German (TKMS-HDW)
competitors.
It
appears that recent performance data on LIBs for submarine are kept very
confidential by all 3 countries, on commercial and national security grounds.
This makes it very difficult to ascertain whether any of the 3 have superior
LIBs.
The
US may also be developing LIBs that may be useful for submarine use. It is
unknown whether the US Government (and US private industry) would exchange more LIB
technical information with the US’s Pacific ally, Japan, or its NATO allies,
Germany and France.
S’s TRANSLATION OF A JAPANESE DOCUMENT
“FY2006
Policy Evaluation Report (Result of Policy Implementation)” by Department of
Finance & Equipment from Oct/2006 to Mar/2007
Project
Name: Research on new main batteries for submarine
Policy
System: I-4-(2)-2 Research (Development)
Abstract:
We
studied high performance main batteries as main batteries for next submarine,
which is alternative of current lead acid batteries, and got necessary
technological data.
Budget:
About 4,6 billion yen
Evaluation
1. Aim of Project
Lead
acid batteries have drawbacks such as heavy weight, large volume, cumbersome
treatment and long charging time. The aims of this project are to study lithium
ion batteries with high energy density as main batteries for next submarine,
and to demonstrate their feasibility and effectiveness.
2. Status of Achievement
Effect
of Achievement
We
established technology base of large lithium ion batteries with high
capacitance for main batteries of submarine by achieving following
technological terms (a-d). We obtained technological data on performance,
safety and life of submarine main batteries, which would contribute to
enhancement of stealth ability, motion performance and attack avoidance
ability, extension of submerging period, and improvement of maintenance
(a)
Energy density
By
adopting lithium ion batteries, we realized new batteries with twice higher
energy density per unit weight volume than that of lead acid batteries.
(b) Charging
efficiency
We
confirmed that lithium ion batteries showed more efficient charging and lower
reduction in capacity at high efficient discharging than lead acid batteries.
(c) Safety
We
confirmed that lithium ion batteries ensured designed safety in overcharging,
overdischarging and external short circuit situations.
(e) Repeatable
numbers of charge and discharge cycle
We
confirmed that lithium ion batteries showed 1.5 times larger repeatable numbers
of charge and discharge cycle than lead acid batteries, having excellent life
time.
(2)
Period of Achievement
We
started research trial in 2002, finished laboratory testing by 2005.
(3)
Profit
In
this research, we have tried realization of lithium ion batteries with high
capacity considering implementation and established new technology base in a
short period.
["S" in Comments
[October 12, 2015 at 5:22 PM] indicated (along the lines) that Japanese
research on new main batteries for submarine revealed that the energy density
of LIBs was twice that of LABs and lifetime of LIBs was 1.5 times that of LABs.
But, from analysis of “Life Cycle Cost (LCC) Management Reports on
23SS (LABs-Soryu) (see Soryu Table) and 27/28SS(LIBs-Soryu)” and other budget papers, S concludes
that the life time of current LIBs will be twice that of LABs [that is higher
than "1.5 times"] and that prices of LIBs will be high. When adding 24-years
of operational life of 22 Japanese submarines with 30-years operational life of
the 8 Australian submarines, more than 300,000 LIB unit cells will be needed.
There may be a reduction in the price of LIBs caused by mass production
effects.]
A
good commentary on Submarine Lithium Ion
Batteries is at Asia-Pacific
Defence Reporter (APDR) October 2015 edition, Vol. 41, No.8, pages 46 to 48.
EXPRESSIONS
OF INTEREST "SEA
1000 JAPANESE GOVERNMENT & INDUSTRY"
Building a submarine is clearly a complex matter with 100,000s of parts and aspects.
"According to NDS Z 2003 C (2) (Standards of Ministry of
Defence: Non-destructive inspection of war ship steel and classification of its
result), following non-destructive inspections are needed for steel; i)
magnetic particle inspection, ii) dye penetrant inspection, iii) ultrasonic
testing, and iv) radiographic testing. Qualification from level 3 to level 1 is
required for each inspector."
For "3. Building" item "02. Welding" Inspection Service" it does not go down to the level of detail on whether Gas Tungsten Arc Welding (GTAW) of pressure hull naval steel NS110 is required. By way of explanation at
Comments [October 16, 2015 at 12:42AM] S advised "NDS Z 2004 C (Non-destructive inspection of weld zone of
war ship steel and classification of its result) is commonly adopted steels
including NS80 and NS110. NDIS0601 or JIS Z 2305:2013 (Non-destructive
testing-Qualification and certification of NDT personnel) is adopted for the qualifications of an inspector. ISO 9712:2014, which is ISO version of JIS Z
2305:2013 will be adopted for an Australian inspector.
Some anonymous advice is "the MOD may release a list of subcontractors which is partially disclosed. Translation and
understanding of NDS (MOD Standards) are also very important. There are so many
things to do."
IMPROVED SNORKEL
The MOD has highlighted some of its research achievements in its "Technical Research & Development Institute, R&D, Department of Development" website at http://www.mod.go.jp/trdi/en/research/gijutu_senpa_en.html . Highlights include Sonar System for Next-Generation Submarines, Heavy Weight Torpedo G-RX6 and Snorkel System for Next-Generation Submarines.
Snorkel System for Next-Generation Submarines shortened as Improved Snorkel comes with this diagram and description:
"In order for our submarines to
cope with the future situation properly, we are also developing and
implementing the snorkel power generation system which to be smaller size and
higher power to make platform more silent and covert." (Photo and text courtesy Japanese Ministry of Defence)
--
The
most publicised advantage of the Improved Snorkel system for the future Soryu
is its ability to operate in typhoons/major storms, often described as higher
sea states.
An equally important, though lesser known innovation, is its higher power allowing snorts to be quicker, thus reducing the near surfaced danger period. The ability of LIBs to be charged more quickly than lead-acid batteries is a major advantage. The smaller size of the snorkel should reduce the chances of it being seen visually or by radar.
In Comments [at October 15, 2015 at 12:42 AM] S advised (along the
lines) There is very little information
on the Improved Snorkel. S estimated air intake velocity for the big
snorkel. The diameter is estimated from a picture of snorkel
and the statement from the Japanese Navy the “snorkel of the Soryu is as big as a drum”. When that snorkel it operating to two Soryu standard 12V/25/25SB diesel
engines the maximum intake velocity at full power operation is very fast
(135km/h). Even in gentle rain, but not substantial wave conditions, kilograms
of water will be introduced into the snorkel in an hour at a 135km/h intake
velocity. The design of the Improved Snorkel system is a critical factor for quick charging the LIBs."
S added "By the way, acoustic stealth performance is not expected in snorkel operation. MAN diesels show
100-115DB of noise, I do not think that new KHI diesel engine will show drastic
reduction in noise. Current 12V/25/25SB generates terrible noise in surface operation.
Also huge amount of exhaust bubbles from the snorkel generates easy-to-detect noise.”
Comment
A stealthy snorkel system may disperse diesel exhaust
better in the water so it is less easily chemically “sniffed” by manned aircraft,
UAVs, surface craft or other sensors. Heat/infra-red signature or water
disturbance by snorkel, exhaust or snorkel wake may be less. Snorkels can be
better camouflaged for night, day and storm use. Snorkels can be better
streamlined allowing a submarine to operate on snorkel more
quickly through the water. Perhaps a snorkel can be made taller, allowing “snorting”
at a deeper-safer depth for the main sail and main hull of the submarine.
Pete