In an earlier blog article I described my worry that one of my four Seed SenseCAP Solar Node P1-Pro repeaters (seen at right, at an elevation of around 10000 feet or around 3000 meters) might have power problems. I worried that maybe the batteries were no good, or that the solar panel was weak, or that the charging controller was not doing its job right. I had to hike up to the remote location of this repeater and swap it out with a spare.
I have now had an opportunity to do testing on the ailing repeater. A first bit of good news is that with some simple charge-cycling, the repeater now has no difficulty charging fully. And a second bit of good news, as I discuss here, I have learned that Seeed uses really good batteries in this repeater.
First a bit of background. The Harbor Breeze repeater has a single 18650 battery that claims a capacity of 5.55 Wh, but in actual testing (see blog article) it seems to have a capacity about 3% lower (5.35 Wh). Using a LoRa controller with a quiescent power draw of around 6mW, the battery might run down in a few days (assuming no light reaching the solar panel or a temperature that fails to get above freezing).
In contrast, this Seeed SenseCAP Solar Node P1-Pro repeater contains four batteries, each claiming a capacity of about 12 Wh, thus adding up to around 48 Wh. It might take several weeks to run down these batteries.
When I pulled the ailing repeater out of service, I put its four batteries into my battery tester as described in this article. I ran an automated cycle of charge, discharge, and charge. After this, I found that the repeater has had no difficult maintaining a near-1000% charge under solar power.
But what is particularly striking is what the tester told me about the capacity of these batteries. As you can see at right, battery number 4 turns out to have a capacity of 3398 mAh and 12230 mWh. The alert reader will appreciate that this is better than the claimed capacity of 3350 mAh and 12060 mWh. The other three batteries also tested to have better capacity than the claimed capacity.
I offer my compliments to Seeed for under-promising and over-delivering on these batteries in the SenseCAP Solar Node P1-Pro repeater.
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