RE: Mini Piper wiring question
Most chargers don't include charge leads, because they don't know what you'll need/want. There are many different types of plugs. You need to buy or make up your own leads. It's an annoyance, but also a tradeoff. Do you want an affordable charger, or an overpriced charger and a pile of leads you'll never use?
The red plug on the battery is called a "male JST." You need a female JST, and a set of banana plugs.
Another option is to pull the outer sleeve off the 3-prong connector, it just pops off with some careful pulling, and carefully plug it into the battery, making sure to match red-to-red, black-to-black.