Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP Posting-Version: version B 2.10.1 6/24/83; site alice.UUCP Path: utzoo!linus!decvax!harpo!eagle!alice!wookie From: wookie@alice.UUCP Newsgroups: net.auto,net.rec.boat Subject: Re: Marine batteries Message-ID: <2065@alice.UUCP> Date: Mon, 25-Jul-83 16:54:56 EDT Article-I.D.: alice.2065 Posted: Mon Jul 25 16:54:56 1983 Date-Received: Mon, 25-Jul-83 23:44:38 EDT References: <339@hou5f.UUCP> Organization: Bell Labs, Murray Hill Lines: 29 I think we had better find a battery expert here at Murray Hill for this battery question. It is my understanding that a lead acid battery is best kept fully charged at all times. From time to time if it is unused it should be trickle charged at a very low current (<1 amp?) every couple of weeks. A lead acid battery left at some discharged level will build up hard sulfate on the plates which is not easily converted back to lead peroxide and lead and thus the capacity is reduced. My experience with nickle cadmium batteries however indicates that they are best stored in a discharged state (this info came directly from engineers at General Electric) and that they should be fully cycled from complete charge to complete discharge. Ni-cads exhibit a memory for the amount they are used. If you use you battery grass trimmers for 20 minutes and then leave it on the charger the rest of the week, eventually they will only run for 20 minutes and then die completely. They also tend to crystalize if left on the charger all the time and will not work at all unless you zap them with a very high current for a short period of time (seconds) to break down the crystals. WARNING: This is a dangerous practice as the battery can explode throwing potassium hydroxide all over the place! Anyway in conclusion from what I have read it is best to keep a lead acid battery fully charged at all times and the less you cycle it the longer it will last. A Ni-cad should be fully and deeply cycled or stored in a discharged state. Any experts out there on this subject?? Keith Bauer White Tiger Racing