Dear customer, based on your search for a 12v Lithium or Gel solar battery, I would recommend either the 12V 50AH Rechargeable Lithium Ion Battery - LIFEPO4 for R3600 or the Lithium Ion Battery 12V 50AH for R4389 as excellent options. Lithium batteries offer greater cycle life, better charge retention and are generally more suitable for solar/off-grid applications than lead-acid batteries. Both of these batteries provide 50Ah capacity, but the slightly higher price of the second option may be due to a higher quality battery management system to protect the cells. Please let me know if you need any other details!
