the OP hasn't posted any real data on the battery concerned and you have answers suggesting he is good to go?......yep, you're guessing pal........as for age, i'm very close to you, so you must have started business during the tube days.........glad i don't ask for your advice.......i'd be crashing.
Jaka hit the nail right on the head though as usual...........dump this 3 year old pack and buy a higher capacity pack.........cheap insurance.
i do agree on reading the first link on the old timers post though........1 hour there and you'll learn more than oldtyme man can teach ya with his old time tech.