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).
Instructions on the methods for long-term storage of car batteries.
| Identifier | ExFiles\Box 164\2\ img082 | |
| Date | 5th August 1942 guessed | |
| LAYING-UP OF CAR BATTERIES. Many motorists are now faced with the problem of laying up their car batteries for an indefinite period. If the battery is left without special treatment or attention for more than two or three months, its condition will seriously deteriorate, and by the time six months have elapsed it will be completely ruined. Even under the best conditions of storage, the battery will deteriorate slowly. It is not worth while putting a battery into storage unless it is in good condition to start with, and is not more than 12 to 18 months old. Three alternative methods for laying up a car battery, in order of preference, are detailed below:- Method 1 - Periodical Freshening Charges. The battery should be removed from the car and given a thorough freshening charge, followed by further freshening charges at regular intervals of four to six weeks, and a final one just before recommissioning. For maximum benefit, these charges should be given at the full normal rate, which is 7 amperes for a 100 a.h. battery, 3½ amperes for a 50 a.h. battery, and pro rata for other sizes. Each charge should be continued until the specific gravity readings have remained constant for about three hours. This will probably mean charging for about 10 or 12 hours on each occasion, if the full normal rate is employed. The cells should be topped up with distilled water before each charge, in order to keep the tops of the plates covered with electrolyte. After each charge, the battery should be cleaned up externally and the terminals covered with "Vaseline" or petroleum jelly. Between the charges the battery should be stored in a cool dry place with the terminals disconnected from any outside circuit. If a "trickle charger" with an output of, say, one or two amperes, is available, it is quite permissible to use this for giving the freshening charges. This, however, will involve charging at considerably less than the full normal rate, and will hence mean charging for a proportionately longer time. Deterioration of the battery will be slightly more rapid than if the full normal rate were employed. Continuous trickle charging at a very slow rate is definitely not recommended. This, if maintained for more than two or three months, will cause very rapid deterioration of the battery. | ||