If you want the V curve of a Li batt you get an Li batt.
I agree with Lu.Sochr. I used to be an SLA user for some time and I searched far an wide for a cost effective solution. I found the best SLA for the price was a RITAR EV series battery, these were designed for Electric vehicles. Because I do cargo bikes that tow plenty of weight for long distances I often would drain these below 60% and be lucky to get 8 months use and that was pretty awesome compared to other brands.
These batteries were costing me $400 a pop every 6 to 8 mths. And strapping 4*24ah 7 KG batteries to my frame became a unwanted repetitive task. However I learned a lot.
With 28kg of lead on my frame. My bike stands would break, the bike would fall over too much and wreck other equipment. My tires would get more punctures, and wear more quickly. All this became a hole in my pocket rather than a saving and a hell of a lot of work. At first the work was fun. As I would find a lot of work around's, and learn to build a very strong bike, modify bike stands, and learned much about weigh distribution and braking. My bike ended up weighing over 60kgs and my cargo hauls were increasing every trip.
The v drop you get on any pack, multiplied by the current you pull equals wasted watts. So if your voltage sags by 6v and you pull 20 amps, youre wasting 120 watts and that results in heat inside your SLA. This is why you get slower speeds and shorter life spans at higher rate discharges..
When I moved to Li everything changed. What I had learned using SLA's for 2 years was certainly an asset. But it ended the changing and buying new batteries. I prolly spent about an extra $200 on my LiFePo4 pack, delivery inclusive, shed about 24kgs off my frame, My tires would last longer, and less puncture repairs, new tubes and brake pads, spoke replacements, and with the 15ah Li pack vs the 24ah SLA I gained between over the long term between 2.5-3 * the range.
And also, my Ebike was much safer.
The difference was so noticeable I never looked back.
The old SLA's didnt go to waste though, they are still good for lighter use, for power drills that the pack died. For DIY torches, for solar panels, experimenting with electronics, testing controller and motors. I still am using them old SLAS now years later and recycled a few, its just there are totally useless for EV's..
