Charging lead acid Ebike batteries


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1:46 PM
Dec 19, 2018
Ebikes use sealed lead acid batteries or SLA's not flooded as in car starters. They require the use of a three phase charger. 1st phase is full charge to approx 85 to 90% capacity. 2nd phase is the top up charge, 3rd is the maintenance charge or trickle charge. Most Chinese chargers have two led's a red and a green. In phase one the red led is lit the green is out. In phase 2 the red is lit the green will come on intermittently. In phase 3 the red is lit and the green will stay on blinking briefly as the charger maintains the voltage. When unplugged from battery pack but plugged into the ac plug the red led is lit and the green led flashes of and on quickly. This could also occur with it plugged into a bat pack with a blown fuse or a poor connection at a battery post.
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Sealed Lead Acids are getting a little outdated now, most newer ebikes are using Li-Ion batteries. In fact you can usually find replacement batteries to swap out your old lead acid battery on your ebike. Bear in mind you also need to change the charger over too though. If your ebike charges through the controller then it may not be a simple process. You'd be better off charging the battery directly to the battery terminals rather than through the controller as the controller might only be build to charge the lead acid.