When out backpacking I carry 5 devices that need power: 1) cell phone, 2) headlamp, 3) Steripen water purifier, 4) camera, 5) emergency satellite locator beacon. Keeping all these devices happily powered is what I want to talk about in this and a few following blog entries.
In the past, these devices used a verity of batteries. Managing batteries and spares was a nightmare. Now days I make a point that every device can be charged with a USB plug. So no more spare batteries, instead I rely on a battery pack. This blog entry is about the battery packs, or about the few that I have.
About my battery packs
Brand “EasyAcc”, rated 5000mAh, weight 5oz.
– Charge from 0 to 100% – 2900mAh
– Discharge from 100% to 0 – 1750mAh
– Efficiency (discharge/charge) – 60%
– capacity/weight – 350mAh/oz
Brand “Ravpower”, rated 15000mAh/55.5Wh, weight 11oz.
– Charge 0 to 100% – 12850mAh
– Discharge 100 to 0% – 9500mAh
– Efficiency (discharge/charge) – 74%
– capacity/weight – 863mAh/oz
Note: The Ravpower battery seems to have a problem when charging with a solar panel. Solar panel power fluctuates depending on sun exposure, angle, sky condition, etc. The Ravpower battery will stop charging if the power drops too low and will only resume charging if it is completely disconnected first. I have the same problem with my cell phone.
Brand “Newtrent”, rated 12000mAh@3.7v(44.4Wh), weight 8oz
– Charge 0 to 100% – 8500mAh (9250)
– Discharge 100 to 0% – 6700mAh (6850)
– Efficiency (discharge/charge) – 79% (74%)
– capacity/weight – 837mAh/oz
Note: the Newtrent battery seems to behave fine when charged from a solar panel
notes:
1) Efficiency is important when using a solar charger to charge the battery and then the battery to charge other devices. It is not important when using wall power.
2) Capacity/weight is likely to drop with time. This is important for backpacking, but less so for other usages.
About some of my electronic devices
Samsung Note 4 – rate 3200mAh
– Charge from 15% to 100% (phone is on) – 2800mAh
Steripen Ultra –
– it was down 2 bars (out of 4) after 10 days of hiking from Tuolumne to Donner
– Charge from 2 bars to full – 150mAh
Note: there is no practical way to drain the battery for testing purposes
Headlamp Black Diamond ReVolt –
– it was down to empty after 10 days of hiking from Tuolumne to Donner, used about 2 hours every day
– Charge from empty to full – 450mAh
chugchug 