Tesurty Replacement EB-BT561ABE Battery for Samsung Galaxy Tab E 9.6" T560 T561 SM-T560 SM-T561

Finally got the battery installed as it came eith the neceddary tools for the job and my son was very happy because he could use his tablet again. Imediately it showed that the battery was at 61%. I thought i bought a new battery so how is this possible with a new product?