On 28 Sep 2017 at 16:35, brucedp5 via EV wrote: > If you have to replace your pack, I suggest: > http://www.sears.com/automotive-batteries-marine-batteries/b-1100201 > > select the appropriate size you currently have, either group 31, 27, > or 24. I have had good cycle life with these ...
Careful there! Unless things have changed, Sears and other mass retailers buy their batteries from different suppliers at different times. It probably depends on who bids lowest. So, you might get batteries similar to Bruce's. Or, you might get batteries like the Sears Diehards that went into the earliest Solectria Forces. Many of those failed in less than a year. For flooded marine batteries, I would go with Trojan or US Battery brand instead. At least you'll know who made them, and those two companies have a long history of making good EV batteries. That said, the longest-lived 12v marine batteries I know of are East Penn Deka Dominator gel batteries. I have them in an Elec-Trak tractor and a New Idea riding mower. They're getting close to 20 years old and are just now finally starting to lose capacity and fail. Solectria Force and E-10 road EVs worked them much harder than my tractors, and routinely got over 5 years of life. However, they come with some caveats. 1. They're not high power batteries. Their voltage sags rather alarmingly at high currents. You'll need to keep a light right foot and live with modest acceleration (many would say "slow"). Turning down the controller's current limit would not be a bad idea. 2. They have less capacity than similar flooded marine batteries, so give less range. This is part of the secret to their long life -- you can't overdischarge them because they're acid-starved. The electrolyte turns to water before the girds can be damaged. 3. They need a charger which won't push them over 14.3 volts per battery. I wouldn't recommend using your BC-20. Bruce and Roger have discussed this in more detail. 4. They're not cheap. I didn't notice that Roger mentioned that he is (or was? I don't know his current status) involved with Delta-Q. That's why he can write with authority about their chargers. He knows his stuff! FYI, in case it matters, AFAIK Delta-Q chargers are still designed in Canada and manufactured in China. I somewhat reluctantly agree with Roger's recommendations about modular charging (one charger per battery). Intuitively, it seems like a great idea. But like many others who've tried it, I've used it, and have had an individual charger fail. Fortunately in my case, the pack was only 36v, so I quickly caught the one incompletely-charged battery going flat. The larger the pack, the less chance you have of noticing an undercharged battery before it's too late and that battery becomes what longtime EVDL contributor Bob Rice (RIP) used to call a "Trojan Teakettle." Some other folks here on the EVDL will no doubt tell you that "lead is dead" and that you should convert your EV to lithium. They have interesting arguments. I won't either agree or disagree. David Roden - Akron, Ohio, USA EVDL Administrator = = = = = = = = = = = = = = = = = = = = = = = = = = = = = EVDL Information: http://www.evdl.org/help/ = = = = = = = = = = = = = = = = = = = = = = = = = = = = = Note: mail sent to "evpost" and "etpost" addresses will not reach me. To send a private message, please obtain my email address from the webpage http://www.evdl.org/help/ . = = = = = = = = = = = = = = = = = = = = = = = = = = = = = _______________________________________________ UNSUBSCRIBE: http://www.evdl.org/help/index.html#usub http://lists.evdl.org/listinfo.cgi/ev-evdl.org Read EVAngel's EV News at http://evdl.org/evln/ Please discuss EV drag racing at NEDRA (http://groups.yahoo.com/group/NEDRA)
