Brand names are the first topic of discussion when it comes to batteries. While everyone is comfortable with household brand names like Samsung and Panasonic, these companies also make lower grade batteries. Li-Ion batteries are graded, generally A-C, which is a generalized guide referencing overall power, capacity, and lifespan.
A grade A cell from a lesser known brand of Li-Ion battery will significantly outperform a Grade C cell from a more popular brand name. This is why you see low cost eBikes and significantly more expensive brands touting the same brand name batteries, but one bicycle is much more expensive. Overall, a reputable eBike brand, A or B rated li-ion cells, and a strong warranty are the safest bet to ensure you’re getting the best bang for your buck.