Technology and Operations
This forum is for discussing technological & operational matters pertaining to U-boats.
Re: re charging batteries
Posted by:
BHenderson
()
Date: May 12, 2013 03:41AM
Maciek has given you very good answers. I'd add that in real life, it's hard to be exactly sure where you are. If you draw a lead-acid battery down below about 50% of charge, you'll drastically reduce its life. Also, "full charge" depends on the state of teh chemicals in the battery, temperature and other factors. Also, as Maciek points out, it's necessary to drop the charging amps as you reach the fully-charged state.
Often in war it is necessary to go things you normally wouldn't. You might rev an engine to 110% of its normal output or operate troops for 30 days with 20 days worth of rations. So, you need to know if "fully discharged" is really the state where the chemical condition of the battery is such that it's critically discharged or if you're just down to the state where the L.I. beginning to get nervous. Also, the last few % of charge takes great care to prevent overheating or boiling of the battery fluid ("acid") and takes much more time to accomplish than a similar %-age during the middle of the charging cycle.
So, in the real world, it's a bit of a black art to assess the depletion level, the amount of charge amperage needed, battery internal condition and temperatures, the level of "fully charged" and the way you get there. Throw in external factors, such as whether 4" shells are being lobbed over your head, and exact charging times get pretty hard to exactly predict in real life.
But again, for the technical details arrived at by experience and testing, have another look at Maciek's excellent posts.
BH NC USA
Often in war it is necessary to go things you normally wouldn't. You might rev an engine to 110% of its normal output or operate troops for 30 days with 20 days worth of rations. So, you need to know if "fully discharged" is really the state where the chemical condition of the battery is such that it's critically discharged or if you're just down to the state where the L.I. beginning to get nervous. Also, the last few % of charge takes great care to prevent overheating or boiling of the battery fluid ("acid") and takes much more time to accomplish than a similar %-age during the middle of the charging cycle.
So, in the real world, it's a bit of a black art to assess the depletion level, the amount of charge amperage needed, battery internal condition and temperatures, the level of "fully charged" and the way you get there. Throw in external factors, such as whether 4" shells are being lobbed over your head, and exact charging times get pretty hard to exactly predict in real life.
But again, for the technical details arrived at by experience and testing, have another look at Maciek's excellent posts.
BH NC USA
Subject | Written By | Posted |
---|---|---|
re charging batteries | laboe | 05/10/2013 08:58PM |
Re: re charging batteries | BHenderson | 05/11/2013 08:50AM |
Re: re charging batteries | laboe | 05/11/2013 11:46AM |
Re: re charging batteries | BHenderson | 05/12/2013 03:41AM |
Re: re charging batteries | SnakeDoc | 05/12/2013 09:21AM |
Re: re charging batteries | SnakeDoc | 05/12/2013 12:55PM |
Re: re charging batteries | SnakeDoc | 05/11/2013 12:41PM |
Re: re charging batteries | laboe | 05/11/2013 02:12PM |
Re: re charging batteries | SnakeDoc | 05/11/2013 02:28PM |
Re: re charging batteries | laboe | 05/11/2013 04:03PM |