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The concept behind this concept is that most of the time when deciding on what battery you want to use, you should choose only one. This is clearly unfavourable because in most conditions you'll need to select. Choose the advantages of each of the completely different battery chemistries.

The 2 most useful battery chemistries tend to be Lithium Polymer and Lithium Ion. Lithium Polymer batteries can have very excessive charge and discharge currents due to their low ESR and Lithium Ion batteries can have a much increased energy density. For tons (if not most) cases both qualities are needed. Therefore, it is a pure conclusion that you'll want a mix of the 2. The problem with this is that because they have completely different ESRs. Different working voltage ranges they can’t just be connected in parallel.

If the batteries have been linked in parallel you wouldn't be able to use the complete capacity of the Lithium Ion batteries, as a result of they have a lower minimum voltage of ~2.5V compared to ~3.2V for Lithium Polymer batteries.

Further, in excessive discharge present events more energy could be drawn from the lithium polymer battery pack Polymer batteries due to their lower ESR, and then when the excessive discharge present occasion stops the Lithium Polymer batteries could be left with a lower voltage potential than the Lithium Ion batteries. This in flip would cause a present stream from the Lithium Ion batteries to the Lithium Polymer batteries. It is true that this would solely occur when there's a change in present draw, however this sort of hybrid battery would only be helpful in functions the place current adjustments by large quantities, fairly steadily.

Over time this would trigger extreme put on to each units of batteries and could possibly be harmful, if this extra present stream causes the batteries to overheat and vent. The identical could additionally probably happen when charging the hybrid battery.

Existing Products

So far I have been speaking as if all Lithium Ion batteries are the identical, this isn't true. When I have been referring to Lithium Ion batteries, I have truly been extra specifically referring to Lithium-Cobalt Oxide batteries. These are by far the most typical type of lithium Ion batteries (Here for extra information). For those who have almost any questions about exactly where and tips on how to work with lithium iron phosphate battery pack deal, you can contact us with the webpage. However, extra not too long ago, Lithium-Manganese Oxide Batteries have been becoming extra well-liked as a result of their increased discharge rates, Lipo battery pack in trade for lower power density. This is exactly the identical level that I need to get to with my hybrid battery, however for the time being, Lithium-Manganese Oxide batteries will not be nearly as good as they'd have to be for some functions.

One representative instance is the Samsung INR18650-25R, it has a continuous discharge price of solely 20A and a capacity of only 2500mAh. This is just a slight enhance in capacity compared to a typical Lithium Polymer battery (2200mAh at this weight). It has an enormous decrease in discharge price (easily 60A at this weight).

Although it can be direct ‘competition’ to a hybrid battery, this seems to be a really low bar to clear.

My Solution

My resolution is still to connect the 2 battery chemistries in parallel, however circuitously. Instead, there can be a diode between the Lithium Ion and Lithium Polymer batteries that may stop the Lithium Ion battery from discharging into the Lithium Polymer battery. This diode can be advantageous as a result of the voltage drop throughout the diode would compensate for the lower minimal voltage of the Lithium Ion battery by artificially dropping the voltage of the Lithium Polymer battery.