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Chapter 8: Batteries 197Fi g u r e 8-5 Trojan 5SHP 12-volt deep-cycle batter y.rugged construction, and the stud-type terminal posts with bolts and nuts. This caseand construction is common to all family members in this 6-volt line. Figure 8-5 showsyou a 12-volt unit, the 5SHP model case mockup previewed by Trojan at the September1992 Burbank Alternate Transportation Expo. You might (or might not) have the EVlabel on the batteries you buy from your distributor.Table 8-2 gives you the details of this lineup of five recommended EV battery choicesfrom Trojan. Other than suggested list price—an area that we’ll save for specialdiscussion—this is all from published data that you can get from your local dealer.It lays out everything you need, but doesn’t quite give it to you in the form youneed it—yet. Figure 8-6, also drawn from published data, shows the actual capacityversus time performance charts; notice the similar performance of the 6-volt and 12-voltdata groups. You can use this data to determine the results of applying actual loads toany of the batteries you choose.Figure 8-7 is from actual Trojan data on the T-105 model battery calculated 6/29/92.It is the real-life example of an equation shown earlier:Battery Life Cycles 5 K d/Depth of Discharge InIn this figure K dis around 28,000, so it shows that Trojan technology is pushing itsdeep-cycle batteries into the industrial battery area. In other words, the T-105 modeland its other family members are heavy-duty deep-discharge batteries.To figure out how many batteries you need, first determine the voltage at whichyou are going to operate your EV conversion. This voltage is established from yourchassis, motor, and controller trade-offs, and heavily influenced by ultimate use, longestrange, or fastest acceleration.Our objective here is to pick the best battery for Chapter 10’s actual pickupconversion, so the operating voltage of 120 volts has been selected. Assuming you wantall your batteries of the same type, and also that you’re not going to use any trickyseries-parallel wiring combinations, this means you’ll either require 20 of the 6-voltbatteries or 10 of the 12-volt batteries, all wired in series to obtain the 120 volts. Whenyou wire your batteries in series, the total capacity available—the total ampere-hours—is the same as that available from any one battery. The total watt-hours is simply thetotal voltage times the total ampere-hours. The total weight, cubic feet, and cost is