Sealed Lead Acid vs. Lithium Iron Phosphate
Apr 20th 2023
Lead Acid
Pros:- Use of lead-acid batteries is widespread globally because they are relatively inexpensive to produce.
- These batteries are reliable and can withstand harsh conditions with little or no maintenance.
- Although people view the materials inside as dangerous, the battery is almost 100 percent recyclable. Sulfuric acid is safely neutralizable, and the lead and polypropylene case can make other batteries.
- Traveling with a device that utilizes a lead-acid battery is far less complicated.
- Very affordable - a Group 31 size deep cycle lead-acid battery with 100ah of capacity will cost $150 - $300, depending on type and quality.
- The batteries are too heavy and bulky for a given capacity.
- Lack of proper recycling of the materials could be hazardous to the environment.
- They have a limited lifespan.
- Spillable lead acid batteries are classified as dangerous goods under Class 8 regulations, controlled by UN 2794. This is because of the risk of fire if shorted.
- Shorter lifespan and cycle life than LiFePO4 batteries, especially when they're deeply discharged.
- Discharging deep-cycle lead-acid batteries below 20% (and sometimes 50%) permanently reduces the battery's capacity.
- High current loads rapidly diminish rated capacity...most deep-cycle lead acid batteries are designed for slow, steady discharge over a 20+ hour period. if the time frame is reduced, the capacity rating drops.
Lithium Iron Phosphate:
Pros:- Long life span (5-10 years) vs lead acid (1-3 years), depending on depth of discharge and assuming that the cycle limit doesn't kill the battery first
- Longer cycle life, as LiFePO4 batteries last 1,000 to 3,000 charge and discharge cycles, compared to similarly sized lead-acid batteries, which can range from 200 - 1000 cycles (again, assuming depth of discharge is within recommended limits for both battery types).
- LiFePO4 batteries are less susceptible to problems caused by depth of discharge...a LiFePO4 battery can be dropped to 20% of charge without long-term damage. Most lead-acid batteries lose capacity or cycle life if they're discharged more than 50%.
- Lighter than lead-acid batteries.
- Arguably, LiFePO4 batteries are more environmentally friendly than lead acid.
- Very safe - the odds of a "thermal runaway" (aka battery fire) are very low. The same can not be said of other lithium ion chemistries.
- As mentioned, LiFePO4 batteries are costly.
- LiFePO4 batteries are hard to find. Most must be purchased online.
- Susceptible to damage via overcharging (it's very important to use a charging system that's designed for LiFePO4 batteries if you want to maximize their life).
