Path: ...!3.eu.feeder.erje.net!feeder.erje.net!weretis.net!feeder8.news.weretis.net!fu-berlin.de!uni-berlin.de!individual.net!not-for-mail From: rbowman Newsgroups: alt.home.repair,rec.autos.tech Subject: Re: Solar car battery charger Date: 4 Nov 2024 07:00:37 GMT Lines: 17 Message-ID: References: Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit X-Trace: individual.net XllLsPYJHwOzlUy6fdqKzgHXINAkWp5XN0BouRXO/W3k+H4Kp/ Cancel-Lock: sha1:znlxRIYF3lA1upM0GwUfo/KNcWU= sha256:IyQuSWdpI5iPlCNUZxlba6/LPuuPcOp3JINJEGcffbM= User-Agent: Pan/0.149 (Bellevue; 4c157ba) Bytes: 1578 On Sun, 3 Nov 2024 21:58:11 -0700, Charlie wrote: > What kind of panel do you think I need? > And does it need some kind of control module to charge a car battery? You can cheap out and skip the control module if you keep an eye on the voltage. A little overcharging probably won't hurt not the greatest batteries. Just check the electrolyte levels and keep them up. Put a blocking diode in series with the panel. https://www.homemade-circuits.com/how-to-make-solar-battery-charger/ Some cheap circuits if you know anything about electronics. Solar panels have a nice feature. They are current sources. Short them out and the voltage goes to zero and the current limits to the short circuit current. Obviously you want a blocking diode since shorting a lead acid battery usually is a little dramatic.