From the Rolls-Royce experimental archive: a quarter of a million communications from Rolls-Royce, 1906 to 1960's. Documents from the Sir Henry Royce Memorial Foundation (SHRMF).
Battery life test log sheet showing discharge data.
| Identifier | ExFiles\Box 41\2\ Scan090 | |
| Date | 20th January 1919 | |
| BATTERY LIFE TEST - DISCHARGE DATA SAMPLE #2735 - F2396 DATE OF DISCHARGE | NO. DAYS ON CHARGE | AMPERE HOURS | VOLTAGE MAX. | VOLTAGE MIN. | SPECIFIC GRAVITY MAX. | SPECIFIC GRAVITY MIN. | TEMPERATURE MAX. | TEMPERATURE MIN. | AMP. HR. RATE | REMARKS 11-1-17 | 31 | 5280 | 6.30 | 5.00 | 1.250 | 1.090 | 90 | 64 | 120.62 | 12-3-17 | 63 | 10584 | 6.40 | 5.00 | 1.210 | 1.080 | 84 | 63 | 100.00 | 1-11-18 | 96 | 16128 | 6.30 | 3.60 | 1.225 | 1.100 | 96 | 59 | 95.00 | CENTER CELL DEAD 3-5-18 | 120 | 20160 | 6.50 | 5.00 | 1.280 | 1.105 | 100 | 73 | 130.00 | ELEMENTS CLEANED, ETC. 4-5-18 | 150 | 25200 | 6.40 | 5.00 | 1.250 | 1.110 | 104 | 69 | 112.50 | POSITIVE END CELL LOW 5-3-18 | 180 | 30240 | 6.50 | 5.00 | 1.270 | 1.110 | 100 | 78 | 120.00 | CENTER CELL DOWN 6-3-18 | 210 | 35280 | 6.35 | 5.00 | 1.250 | 1.080 | 104 | 88 | 125.62 | POS. AND CENTER - 1.60V NEGATIVE END - 1.80V 7-5-18 | 240 | 40320 | 6.35 | 5.00 | 1.255 | 1.085 | 112 | 87 | 122.00 | POS. - 1.50V CENTER 1.75V NEG. 1.08V 9-10-18 | 300 | 50400 | 6.40 | 5.00 | 1.250 | 1.110 | 98 | 70 | 92.50 | POS. - 1.80V CENTER 1.40 NEG. - 1.80V 10-14-18 | 330 | 55440 | 6.25 | 5.00 | 1.260 | 1.115 | 102 | 70 | 105.62 | POS. - 1.80V CENTER-1.40V NEG.- 1.80V 11-13-18 | 360 | 60480 | 6.30 | 5.10 | 1.250 | 1.120 | 96 | 72 | 120.62 | 12-17-18 | 390 | 65280 | 6.25 | 5.10 | 1.280 | 1.110 | 98 | 72 | 120.00 | ALL CELLS 1.7 VOLTS 1-20-19 | 420 | 70560 | | | | | | | 15 MIN. | NEG. END CELL DOWN COMPLETELY. CADILLAC MOTOR CAR CO. DETROIT-MICH. ELECTRICAL DEPT. | ||