I know it’s too late for john25 battery as it has already kicked the bucket, but here is a little guide on Lithium-ion battery care.
They call them batteries when they leave china, we call them bombs when they arrive in the UK. Since lithium-ion batteries are so energetic, they get very hot. The heat causes the battery to vent the organic solvent used as an electrolyte. If the battery gets hot enough to caused an internal short, it could ignite the electrolyte and you’re going to get a fire or they can explode. Once that happens inside one of the cells, the heat cascades to the other cells and the whole pack goes up in smoke. It is important to note that fires are very rare though. Lithium-ion battery packs are expensive, so if you want to make them last longer, you’ll have to keep a few things in mind. Lithium-ion chemistry prefers partial discharge to deep discharge. So it's best to avoid taking the battery all the way down to zero. Since lithium-ion chemistry does not have a memory, you won’t harm the battery pack with a partial discharge. If the voltage of a lithium-ion cell drops below a certain level, it's ruined. On average they only last two to three years, even if they are just sitting on a shelf unused. Also, if you’re buying a new battery pack, you want to make sure it really is new. Manufacturing dates are important. If its been sitting on a shelf for a year, it won't last very long. Battery packs usually have one or more temperature sensors to monitor the battery temperature, a voltage converter and regulator circuit to maintain safe levels of voltage and current, a battery charge state monitor, which is a small computer that handles the whole charging process to make sure the batteries charge as quickly and fully as possible and a voltage tap which monitors the energy capacity of individual cells within the battery pack. If the battery pack gets too hot during charging or use, the computer will shut down the flow of power to try to cool things down. One of the cells is used to monitor the system which is why batteries lose 5 percent of their power every month when sitting idle. If this cell ever becomes completely discharged, the battery pack is ruined even though the rest of the pack will be fine. The charger monitor will from then on refuse to charge the pack. Which is what probably happened to john25 battery pack.
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