*S = Standard charge, R = Rapid charge

*S = Standard charge, R = Rapid charge

Back to the Basics

At a dribble, the bucket would be empty in 100 hours.

When the valve is wide open, the bucket would be empty in 1 hour.

Batteries and Buckets

Battery capacity is measured in Ampere-hours at a particular charge/discharge rate (called C rate). I used to find C rates really confusing, so let's find an analogy. Richard often compares a battery to a bucket — you fill it up, use it, and refill it. The bigger the capacity, the more a bucket (or battery) will hold. Now, to talk about charge rates, let's take our bucket and add a valve or hosebib to the bottom. Suppose we turn the valve so a fair dribble of water runs out (obviously watering plants — we won't waste it). And this dribble is such that the bucket is empty in 100 hours. You can imagine a certain rate of water flowing through the valve. If we take the capacity (C) and divide by the time to empty the bucket, we get a rate of C/100. But suppose we turn on the valve some more, so that the bucket is empty in 20 hours. Then the rate would be C/20. Or we could turn the valve wide open and empty the bucket in 1 hour — a C/1 rate.

But a battery is not exactly like a bucket. When the battery reaches its discharge cutoff voltage, that's it. The battery cannot be discharged any further. The discharge cutoff voltage for small sintered plate nicad cells is 1 Volt. The amount a battery can deliver (its true capacity) depends on the rate of discharge (how fast the electrons are moving out of the "valve"). A capacity figure (100 Amp-hours) is followed by a C rate to tell you what the capacity is when the battery is discharged

DIY Battery Repair

DIY Battery Repair

You can now recondition your old batteries at home and bring them back to 100 percent of their working condition. This guide will enable you to revive All NiCd batteries regardless of brand and battery volt. It will give you the required information on how to re-energize and revive your NiCd batteries through the RVD process, charging method and charging guidelines.

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