This is a classic case of why voltage readings are not a conclusive test of battery health, and why we invested so much into a proper battery tester.
This was a pair of 20AH Sealed Lead Acid (SLA) batteries. Voltage readings were 13.11 V and 13.12 V for each battery, respectively, and batteries were only 5 months old. Most technicians from other companies would have passed these batteries as healthy and ruled them out as a problem.
But from experience, we know that roughly 10% of problems cannot be detected on-site by simply by measuring voltage. You must run a discharge test and study the graph, similar to how a cardiologist studies an Electrocardiogram (ECG).
These batteries are among that 10% of defective batteries with problems that multi-meters cannot detect. We have replaced the client's batteries under warranty.
If you suspect that your mobility scooter or electric wheelchair's batteries are no good, and your vendor insists that they are OK, please feel free to contact Falcon Mobility for a 2nd opinion. But kindly note that a diagnosis fee of $70 applies.
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