October 24, 2019

Nickel-Zinc Main Batteries Unsuited to Submarine Use

Lead-acid batteries (LABs) have been used for submarines for over 100 years and it appears they will unquestionably be used for Australia's future Attack-class submarines.

If replacement battery technologies were considered? There is a debate in Australia about the suitability of using 100 year old Nickel-Zinc (NiZn) battery technology for these future submarines rather than using newer technology Lithium-ion Batteries (LIBs).

Anonymous does not think NiZn is suitable for submarines.

There are two issues (A. short lifetime [1], and B. low voltage) in NiZn battery applications for submarines. 

A. The biggest issue is short battery life. Charge/discharge cycles for NiZn is only 200-300 times. 

Snorkeling of a submarine (with LABs) is conducted at least once a day. 

If the annual availability rate of submarine is 60% (ie. 200 mission days per year) then NiZn main batteries would need to be replaced once a year. This is unrealistic on cost grounds. 

NiZn's 200-300 cycles can be compared to:
-  7,000-15,000 cycles for Japanese LIB-NTO technology,
up to 4,000 cycles (10 years of use) for South Korean LIBs technology. and
2,000 cycles for LABs but with LAB's disadvantages compared to LIBs including lower LAB voltage (power)/weight as well as shallower and slower charging (higher LAB indiscretion ratio).

B. Also, the voltage (power) of a NiZn battery (1.6V) is lower than LABs (2V) and LIBs (3.6V).

[1]  https://batteryuniversity.com/learn/article/nickel_based_batteries see Nickel-zinc (NiZn) subheading

Comment

As NiZn batteries have been around since 1901 one would have thought NiZn would have been adopted well before now if LiZn were a serious contender.

Anonymous and Pete

2 comments:

MHalblaub said...

Dear Pete,
the low lifecycle is no longer a problem. I use AA and AAA sized NiZn batteries and they work rather fine compared with NiNH batteries. For many applications 1.6 V are much better than 1.2 V NiMH. Voltage is no issue with series circuits and a custom built layout.

The big main issue with NiZn is a delicate loading process that takes a rather long time. Even longer than for lead acid batteries.

The main issue is to reload the batteries on a submarine in a rather short time. The question therefor is not how much energy per weight rather than how much energy per weight within an hour snorkling.

Regards,
MHalblaub

Pete said...

Hi MHalblaub

Yes there are so many comparative issues between large scale LABs, LIBs and NiZn batteries that take years and many $millions in land-based tests.

This would have particularly occurred in Japan from 2012 (when looking at the Table at https://gentleseas.blogspot.com/2019/03/aip-libs-difference-on-japanese.html ). In 2012 no Japanese submarine was launched and instead likely the equivalent of US$500 million in submarine LIBs development funding began to be spent.

Seabased tests then become even more thorough and expensive than landbased tests with hundreds of tonnes LIBs on a Japanese test-"training" submarine or two.

Regards

Pete