This HI-TEC charger can charge 4 packs at a time.
I charge my packs at a slow rate - Never a "fast charge",
and inside a fire proof box.
| 1. |
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I first started using lead acid batteries in my robot designs, but they were very heavy. When I heard that electric cars were being built with lithium ion cells, like those in a laptop, I decided to use lithium ion, 18650 cells. |
| 2. |
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Lithium ion battery packs, as used by RC cars and airplanes are expensive, and they are built tightly packed in tape and shrink-wrap. If one cell goes bad, they are very difficult to repair. |
| 3. |
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I want to be able to easily replace a single bad cell, and build cell packs where each cell has a similar internal resistance. As cells age, their internal resistance can change. I can easily build packs where all cells in series have a matching internal resistance. This extends the time that a pack can maintain a good voltage level when in use. |
| 4. |
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Many parts in my robot are automotive parts that require 12 volts, and my main motors can run on up to 24 volts. To produce 24 volts from fully charged (4 Volts) lithium ion cells, I need six cells in series, but I could not find cell holders that would hold six 18650 cells. So, I built my own. |
| 5. |
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Three cell packs, bundled together. |
| 6. |
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Each cell holder has banana jacks for the main current, and a balance port connector. |
| 7 |
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The balance port connector can also be used to insert a "volt meter / low battery alarm" that can display the voltage of each cell, and a total. |
| 8 |
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The cell holders have additional connections to each individual cell, so that the entire pack
can be "Balance Charged" by a RC LiPo charger. This HI-TEC charger can charge 4 packs at a time. I charge my packs at a slow rate - Never a "fast charge", and inside a fire proof box. |