When to Put in New Plates
1. If one or more jars are cracked and leak, and positive plates have been ruined by freezing, as shown in Fig. 203, and if upon drawing out the separators, and separating the positive and negative groups the active material drops out of the grids, the only way to put the battery in a good condition is to put in new positives, and new jars and case if necessary.
Make a careful estimate of
(a) Cost of new jars.
(b) Cost of new plates.
(c) Cost of new case if needed.
(d) Cost of labor required.
Try to have the owner present while you are opening his battery. If, however, he could not wait, and has left, call him up and tell him what the total cost will be, and if he has no objections, go ahead with the job. If he is not entirely satisfied with your price, try to get him to come to your shop. Show him the battery, explain its condition, tell him just what must be done with it, and explain how you made your estimate of the cost of the whole job. If you do this. there will never be any misunderstanding as to cost. Tell him the cost of a new battery, and let him decide if lie wants one. If the cost of repairing is almost as much as the price of a new battery. advise him to buy a new one, but allow him to make the decision himself. He will then have no cause for complaint.
Fig. 204 and 205, Show Diseased Negatives. The Large Ones Only Eight Months Old. Active Material, Granulated and Blistered.
2. If the battery is more than two years old, and the active material on the negative plates is granulated (grainy appearance), Figs. 204 and 205, and somewhat disintegrated; if the plates are weak and brittle around the edges, and several grids are cracked, Fig. 206, and the plates have lost a considerable amount of active material; and if the case has been rotted by the acid, the battery should be junked.
Call up the owner, and tell him he needs a new battery. If he does not seem pleased, ask him to come to your shop. Then show him his battery, and explain its condition. If you are courteous and patient, you will sell him a new battery. Otherwise he will never return.
3. If the positive plates are badly distorted from buckling, as in Figs. 207 and 208 discard them, for they will cut through new separators, if put into commission again, ill from two to six months.
4. A battery which has has been dry and badly sulphated at some past period of its life will have the dry portions covered with a white sulphate, the acid line being clearly distinguishable by this white color, as shown at A and B in Fig. 201. If the plates are otherwise in good shape and you wish to use them, give them the “water cure” described on page 349.
5. Rotten and disintegrated positive plates, Figs. 209 and 210, must be replaced with new plates. The plates have fallen to pieces or break at the slightest pressure. Disintegrated plates are an indication of impurities or overcharging, providing the battery is not old enough to cause disintegration normally,—say about two years. The lead grid is converted into peroxide of lead and becomes soft. As a result, there is nothing to support the paste, and it falls out. Better put in new negatives also.
6. Batteries with high gravity or hot electrolyte have burned and carbonized separators, turning them black and rotting them, the negative paste becomes granulated and is kept in a soft condition, and gradually drops from the grids on account of the jolting of the car on the road. Fig. 211 shows such a battery.
7. Dry, hard, and white, long discharged, and badly sulphated plates, Figs. 201 and 209, are practically ruined, though if the trouble is not of long standing, the plates may be revived somewhat by a long charge at a very low rate, using distilled water in place of the electrolyte, and then discharging at a current equal to about one-eight to one-tenth of the ampere hour capacity of the battery at the discharge board. Charge and discharge a battery a number or times, and you may be able to put a little “pep” into it. In charging sulphated plates, use a low charging rate, and do not allow gassing before the end of the charge, or a temperature of the electrolyte above 110°F.
8. If a battery case is not held down firmly, or if the elements are loose in the jars, the plates will jump around when the car is in motion. This will break the sealing compound on top of the battery, and cause the battery to be a slopper. The active materials will be shaken out of the grids, as shown in Fig. 212, and the plates will wear through the separators. New plates are required.
9. If Battery Has Been Reversed. Often the plates of such a battery disintegrate and crumble under the slightest pressure. If the reversal is not too far advanced, the plates may be restored (See page 81), but otherwise they should be discarded. This condition is recognized by the original negatives being brown, and the original positives gray.
From the foregoing explanations, you see that most of the trouble is with the positives:
(a) Because the positive active material does not stick together well, but drops off, or sheds easily.
(b) Because the positives warp or buckle, this causing most of the battery troubles.
(c) Because the positive plate is weaker and is ruined by freezing.