Choosing the right battery chemistry for you and your system can be a little confusing at times. Three common battery chemistries offered are Lead Acid (Flooded or AGM-sealed), Lithium Ferrous (LiFePO4), Aqueous Hybrid Ion (AHI). Now let’s talk about what each battery is good for.
A Lead Acid or AGM battery is generally low cost and doesn’t require much maintenance, but in return they offer a lower recharge cycle count. These batteries often times will only be recharged from 50% depth of discharge (DOD) approximately 250 times before replacement is required. They are best used with residential or generally smaller systems. Flooded Lead Acid batteries are the tried and true batteries of the solar industry and cost the least, but require watering. The sealed version, or AGM, does not require watering but costs a bit more.
The Lithium battery is best for On-Demand/Grid-tied power management. This battery type is intended for grid-interactive systems to provide backup power and smart energy management. We are very excited about the potential of these types of batteries. Currently, they are expensive, but we expect prices to drop substantially in the coming years. These batteries are very energy dense, so they take up less space than most batteries for the same amount of energy storage. They are also lightweight and tend to have a much longer lifespan than other common types of batteries.
The great thing about LiFePO4 batteries is their ability to withstand heat and cold much easier than most along with the fact that they can be discharged down to 90% DOD. These batteries offer about 20 times the cycle count of lead acid batteries. Of course this is going to be pricier but they do very well in all weather conditions.
An AHI battery will be best for Off-Grid and Battery-Backup applications. This AHI battery is efficient, 100% non-toxic, non hazardous (no off-gassing), and lasts much longer than typical lead-acid batteries. One of the biggest advantages of AHI batteries is that they work with all existing types of solar equipment including solar charge controllers and inverters. While these batteries are best for backup situations and off-grid systems, they are not ideal for power management. The AHI is extremely tolerant to heat, it can operate at high temperatures with no impact to the lifespan. However, they do need to be operated above 23°F.
With all of this information, we would still love to hear from you and answer any questions you might have!