DIY Solar Power with Will Prowsevideo

12V 100Ah has LESS Capacity than 48V 100Ah!? Beginner tutorial!

August 5, 2022 · 3 min · 189K views

Man gestures explaining battery capacity in workshop

What this video covers

A 48V 100Ah battery holds 4,800 watt-hours — four times the capacity of a 12V 100Ah battery's 1,200 watt-hours, despite sharing the same amp-hour rating.0:35 Will Prowse explains that amp-hours alone are meaningless for comparing batteries across different voltages because capacity depends on both voltage and amp-hours combined.1:06 The correct comparison unit is watt-hours, calculated by multiplying nominal voltage by amp-hours.1:39 A 24V 100Ah battery, for example, yields 2,400 watt-hours — double a 12V 100Ah pack.0:36 Prowse illustrates watt-hour capacity in practical terms: a 1,200Wh battery can run a 600W load for two hours or a 300W load for four.2:26 His recommendation is to skip the amp-hour figure entirely when shopping and instead read the watt-hour rating from the battery's manual or label, then compare that number directly across products.2:39 The practical takeaway: a 48V 100Ah battery at $1,500 is not comparable to a 12V 100Ah battery — it contains four times the energy.0:44

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