Product Refresh: Guide 10 Plus Review

In Late October, Goal Zero released a refreshed version of their Guide 10 battery pack, and dubbed it the Guide 10 “Plus.” This refresh was mainly produced to provide higher output in order to supply power to tablets but was also rumored to include a fix for the troublesome charge indicator on the original G10. I’ve put the G10+ through the same tests I put its older brother through.

Here are the results.

Getting straight to the point, the new G10+ seems to have the exact same charge indicator issues as the G10. Despite the G10+ charging and performing just as exceptional as the original G10, you shouldn’t expect the G10+ to ever accurately indicate the charge of NiMH cells contained inside. Here are some sample results.

Sample Test 1. Four 1900mAh Eneloop cells. Charge percentages are measured under the pulse load test. Before charging, one cell was at 40%, one cell was at 20%, and two cells were at 10%. The experiment was performed in ideal weather conditions, with the panel perpendicular to the sun, and adjusted as necessary without obstructing light. Results are as follows:

• 0 minutes – Red Blinking LED (indicating <50% overall charge)
• 30 minutes – Red Blinking LED (indicating <50% overall charge)
• 1 hour – Red Blinking LED (indicating <50% overall charge)
• 1.5 hours – Red Blinking LED (indicating <50% overall charge)
• Test terminated at 1.5-hour mark, cells measured immediately

After charging, all cells indicated 100% immediately after removal from the G10+. Thirty minutes later, after letting the charge settle, the cells still indicated 100%. Additionally, after several days of storage and inactivity, all the cells still indicated 100%.

Clearly the G10+ is charging the cells to 100% but not indicating it, just as the original G10 does. However, unlike the G10, the G10+ recommends you charge cells for 3 hours (as opposed to 1.5 hours) to receive a full charge indication. I decided to put that to the test next, this time with cells that are drained through the G10+.

I’ve noticed that when you are using the G10+ to output charges to devices, the G10+ stops charging the device when it detects a 35% charge throughout. Therefore, draining the cells through the G10+ does not drain them as much as using them directly in other units. I thought that perhaps this was how Goal Zero was determining their charge times, so I drained them to that standard, and retested for 3+ hours. Results are as follows:

Sample Test 2. Four 1900mAh Eneloop cells. Charge percentages are measured under the pulse load test. Before charging, one cell was at 20%, and four cells were at 40%. The experiment was performed in ideal weather conditions, with the panel perpendicular to the sun, and adjusted as necessary without obstructing light. Results are as follows:

• 0 minutes – Red Blinking LED (indicating <50% overall charge)
• 1 hour – Red Blinking LED (indicating <50% overall charge)
• 2 hours – Red Blinking LED (indicating <50% overall charge)
• 3 hours – Red Blinking LED (indicating <50% overall charge)
• 4 hours – Slow Blinking Green LED (indicating 50-80% overall charge)
• 5 hours – Slow Blinking Green LED (indicating 50-80% overall charge)
• Test terminated at 5-hour mark, cells measured immediately

After charging, all cells indicated 100% immediately after removal from the G10+. Thirty minutes later, after letting the charge settle, the cells still indicated 100%. Additionally, after several days of storage and inactivity, all the cells still indicated 100%.

So, the G10+ is still unable to get the elusive solid green full charge indication. In fact, the G10+ is behaving exactly as the original G10. It is charging empty cells in 1.5 hours reliably, but displaying the charge incorrectly just as reliably.

Unfortunately, it seems the rumors are wrong. The only update relative to the charge indicator on the G10+ is a recommendation to charge cells for 1.5 hours longer. The only tangible benefit to the G10+ seems to be its capability to charge higher consumption devices, which I have not yet tested.

The lack of accuracy on the charge indicator is a nuisance, but the actual charging capability is undeniable. Despite its single shortcoming, I continue to use the G10+ on a weekly basis, and trust both the G10+ and the G10 with all my solar charging needs. Relative to the market, I still believe these are still the most reliable portable solar products available today.