This carried a lifetime guarantee, yet found to have failed within 5 years 8 months from purchase. Car last used October 2023. Car has a battery isolator switch, which is off when not in use, along with a Desulfator. (Isolator, car electrics  & Desulfator all checked & appeared okay) Max amp reading after charging early December 300A  14.5 volts, which falls quickly when charging (RING) Auto charger disconnected. Retailers advised on account battery had not failed shortly after purchase. this not a manufacturing fault & battery warranty voided. Efforts to contact YUASA UK have to date proven unsuccessful, with as yet, no response from their side. The now equivalent YUASA batteries carry only a 5 year guarantee, again begging question why ? Car started with no problem when connected to an old Exide battery (450A), confirming electric system fine

Drago V Answered question December 29, 2023