Battery
The battery being tested is a Nautilus flooded Marine/RV battery.
| Specification | Value |
|---|---|
| Make | Motomaster Nautilus |
| Model | 010-2799-4 |
| Capacity | 80Ah(20h) |
| Group | 27 |
Charging Our Battery
We will charge this battery with our Suaoki ICS4 4A battery charger.
| Charging Parameters | Value |
|---|---|
| Battery Type | SLA (includes Flooded) |
| Speed | Fast (4A) |
| Max Voltage | 14.4v |
| Current | 4A |
Charging Steps
Permanent capacity loss can be minimized with operating at a moderate room temperature and a float voltage of 2.25–2.30V/cell (13.5-13.8V).
Discharge Test
A discharge test was performed using the SkyRC Max B6 charger. In order to get the test to run to completion, we had to disable the Capacity Cut off and the Safety Timer (See appendix).
We will use the NiCd Discharge test setting the discharge end voltage to 10.8v. The discharge test will draw 0.5A per hour until it reaches it's cutoff voltage of 10.8v.
First Discharge Test
For this discharge test, we first charged it fully and then discharged it. We discharged it using the using the Lead Acid discharge with no cutoff voltage. Should have used the NiCd discharge test but didn't know to use that at the time.
This discharge test revealed that the battery had a capacity of 6579 mAh (6.6Ah) as opposed to the expected 80Ah. We are only getting 8% of the rated capacity!
| Test | Capacity (mAh) | % of Capacity |
|---|---|---|
| Initial Test | 6579 mAh | 8% |
Next Steps
We discovered that the water levels in this battery were very low. Added distilled water about 1/4" above the plates.
(It's hard to visually see the water level. Perhaps we could use a stick or something next time to check the level.)
Test Results:
| Test | Final Voltage | Capacity (mAh) | % of Capacity | Changes |
|---|---|---|---|---|
| Oct 27, 2019 | 10.16 | 13,392 | 17% | Added distilled water |
| Nov 1, 2019 | 8.69 | 22,226 | 28% | Added more distilled water |
| Nov 7, 2019 | 10.0 | 24,543 | 31% | Shook |
| Nov 12, 2019 | 10.5 | 27,291 | 34% | Shook |
| Nov 18, 2019 | 10.5 | 29,315 | 37% | Shook |
| Nov 24, 2019 | 10.5 | 30,847 | 39% | Shook |
| Nov 30, 2019 | 10.6 | 32,413 | 41% | Shook |
Questions
- Does a lead acid battery rated at 80Ah actually give you 80Ah??
This battery is rated to deliver at 80Ah over a period of 20h which translates to 4A/hour for 20 hours until it reaches 10.5v.
Conclusions
We managed to get our battery back up to about 40% of it's rated capacity and in the process discovered:
- we had been charging our battery as an AGM battery which charges at 14.7v as opposed to 14.4v
- we need to check the water levels of our battery yearly.
Appendix
Disabling Safety Timer and Capacity Cut Off on IMAX B6
In order to get the test to run to completion, we had to disable the Capacity Cut off and the Safety Timer.
Reference
| Reference | URL |
|---|---|
| IMAX B6 Manual | http://www.ittgroup.ee/files/IMAX_B6_manual.pdf |
| How to Check Car Battery Water Levels | https://www.wikihow.com/Check-Car-Battery-Water-Levels |
| Lead Acid Battery Comparison | https://www.wholesalesolar.com/blog/lead-acid-battery-comparison/ |