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Post by Jim on Apr 19, 2021 20:35:04 GMT
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Post by tonyb on Apr 20, 2021 6:53:51 GMT
They have and probably are used today and I think one contributor elsewhere uses them. The hydrogen thing is the same for lead acid batteries, it's the electricity electrolysing the water in the electrolyte into hydrogen and oxygen. The higher the current the more gas is produced.
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Post by JohnV on Apr 20, 2021 7:23:14 GMT
They are one of those "almost" technologies.
Pretty bomb proof but they have a fairly low power density, are heavy for their power output, very high self discharge rate (don't hold their charge well) and are also pretty inefficient (you need to put a lot more charge in compared to what you can get out) and that is rather important for boats. They are not quick charging (although the time to fully charge is very dependent on how much there is left in them) think the time from flat to full is around 8 hours ...... can sort of fast charge but it needs to be done very carefully, so normally you don't.
They are very good for battery banks that are continuously charged at a low rate. In my opinion apart from being extremely robust, they were only marginally better than Lead acids in some ways and were worse in others. (although they did last .... and last ...... and last )
Don't think I have seen any in use for many years ....... IMHO pretty well overtaken by recent battery developments
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Post by Isambard Kingdom Brunel on Apr 20, 2021 7:51:48 GMT
Were not submarine batteries NiFe in the past? They have a very long life and are very robust about being charged and heavily discharged.
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Post by JohnV on Apr 20, 2021 12:27:52 GMT
Were not submarine batteries NiFe in the past? They have a very long life and are very robust about being charged and heavily discharged. I've not heard that, but a one advantage would be that if salt water got in, at least they wouldn't produce chlorine gas. I did read somewhere or other that they were used in locomotive/tram systems (think I did anyway) |
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Post by peterboat on Apr 20, 2021 12:31:52 GMT
Why bother when LifePo4s are so much better in every respect
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Post by JohnV on Apr 20, 2021 12:32:35 GMT
Were not submarine batteries NiFe in the past? They have a very long life and are very robust about being charged and heavily discharged. I've not heard that, but a one advantage would be that if salt water got in, at least they wouldn't produce chlorine gas. I did read somewhere or other that they were used in locomotive/tram systems (think I did anyway) DOH !!! just re-read that !!! silly bugger !!! the chlorine is not produced by the chemical reaction of the battery materials ..... it's caused by electrolysis of the bloody sea water !!!
would be just the same !!! .................. logopodia !!! ( from logos = mouth and podia = foot ie foot in mouth disease ) I blame it on age !!!
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Post by kris on Apr 21, 2021 11:03:26 GMT
This boat came with about 1ton of old Lucas knife batteries. They could have been regenerated. The cases where solid and robust. The reasons outlined by John and the low cell voltages are the reason I sold them and didn’t reuse them.
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